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2. Direct detection of auroral and equatorial jets in the stratosphere of Jupiter with ALMA

Author

Ladislav Rezac, James Sinclair, Thierry Fouchet, Thibault Cavalié, Michel Dobrijevic, Christopher Jarchow, F. Billebaud, Vincent Hue, Emmanuel Lellouch, Randall Gladstone, Raphael Moreno, Paul Hartogh, Thomas K. Greathouse, and Bilal Benmahi

Subjects
Jupiter, Physics, Astronomy, Stratosphere
Abstract

The upper tropospheric zonal winds have been measured since decades using cloud tracking with maximum winds speeds of ∼ 100 m/s in the tropical region (Ingersoll et al. 1979). Juno measurements have shown that these winds extend in the deep layers of the planet (Kaspi et al. 2018). In the ionosphere, jets have been detected in the auroral zone with velocities of 1-2 km/s (Rego et al. 1999). In-between these atmospheric regions, in the stratosphere, there are no such tracers as clouds. Even if zonal winds can in principle be indirectly derived from temperature field by assuming the thermal wind balance (e.g. Flasar et al. 2004), this technique relies on a boundary condition often taken as the cloud-top structure which is located at levels that are separated from where the stratospheric temperature field is constrained. Also, this technique breaks down at equatorial latitudes.Using the Atacama Large Millimeter/submillimeter Array, we mapped Jupiter’s stratospheric HCN emission in March 2017 to directly measure wind-induced Doppler shifts on the spectral lines. We imaged the HCN limb emission with an angular resolution of 1” and a very high spectral resolution. After subtracting the rapid rotation of the planet from the Doppler shifts measured on the spectral lines, we derived the wind speeds as a function of latitude on both limbs.We find strong tropical jets at 1 mbar with velocities of 100-200 m/s lying atop the layers where the Quasi-Quadrennial Oscillation occurs. Most surprisingly, we find strong non-zonal winds in Jupiter’s polar regions at 0.1 mbar with counter-rotation velocities of 300-400 m/s. Their position coincides with the location of the main auroral oval.In this paper, we will present our observations and results. We will also discuss their implications on the dynamics and chemistry of Jupiter’s stratosphere.

Published
2021

3. Subsurface properties and early activity of comet 67P/Churyumov-Gerasimenko

Author

Samuel Gulkis, Mark Allen, Paul von Allmen, Gerard Beaudin, Nicolas Biver, Dominique Bockelée-Morvan, Mathieu Choukroun, Jacques Crovisier, Björn J. R. Davidsson, Pierre Encrenaz, Therese Encrenaz, Margaret Frerking, Paul Hartogh, Mark Hofstadter, Wing-Huen Ip, Michael Janssen, Christopher Jarchow, Stephen Keihm, Seungwon Lee, Emmanuel Lellouch, Cedric Leyrat, Ladislav Rezac, F. Peter Schloerb, and Thomas Spilker

Published
2015
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4. Observing atmospheric HCN on Titan from space and ground-based observatories: an inter-comparison study from Herschel, APEX and IRAM 30m telescopes

Author

Denis Shulyak, Miriam Rengel, Christopher Jarchow, Hideo Sagawa, Paul Hartogh, and Raphael Moreno

Subjects
symbols.namesake, Comparison study, symbols, Astronomy, Titan (rocket family), Geology
Abstract

In support of the Herschel Space Observatory and in the framework of the program “Water and Related Chemistry in the Solar System” [1], hydrogen cyanide (HCN) on Titan was observed from ground at submillimetre wavelengths. We carried submm heterodyne spectroscopy observations of HCN (4-3) at 345.5 GHz with the Atacama Pathfinder Experiment (APEX) and the APEX-2 heterodyne receiver, and of HCN (3-2) at 265.9 GHz with the Institut de radioastronomie millimétrique (IRAM) 30-m telescope (IRAM 30m) and the Heterodyne Receiver Array (HERA) receiver in Titan atmosphere. Observations were carried out on June 16, 2010, and March 19, 2011, under non-favorable and favorable weather conditions, respectively. We report here the APEX and IRAM 30m observations, and by using a line-by-line radiative transfer code and the least-squares fitting technique, the analysis to infer the HCN abundance. Our HCN mixing-ratio estimations confirm the result of Marten et al. (2002) [2]. We compare our results with the those with Herschel/PACS and SPIRE acquired during 2010 [3,4]. Measured HCN abundances on Titan with data acquired at different epochs and transitions exhibit similar abundance distributions. Beyond the intrinsic scientific interest, these observations proven their usefulness in supporting spacecraft observations of Solar System bodies, in particular, of Titan’s atmosphere. [1] Hartogh, P.; Lellouch, E.; Crovisier, J., et al. 2009, Planetary and Space Science, Volume 57, Issue 13, p. 1596-1606. [2] Marten, A.; Hidayat, T.; Biraud, Y. et al. Icarus, 2002, Volume 158, Issue 2, p. 532-544. [3] Rengel, M.; Sagawa, H.; Hartogh, P., et al. 2014, A&A, 561. [4] Courtin, R., Swinyard, B. M., Moreno, R., et al. 2011, A&A, 536, L2.

Published
2020

5. Spatially resolved evolution of the local H 2 O production rates of comet 67P/Churyumov-Gerasimenko from the MIRO instrument on Rosetta

Author

Wing-Huen Ip, N. Biver, Ladislav Rezac, P. von Allmen, David Marshall, Paul Hartogh, Dominique Bockelée-Morvan, Mark Hofstadter, Christopher Jarchow, Pierre Encrenaz, Jacques Crovisier, Samuel Gulkis, Seungwon Lee, Emmanuel Lellouch, Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Institute of Space Science [Taiwan], National Central University [Taiwan] (NCU), Department of Electrical Engineering (DEE-POSTECH), Pohang University of Science and Technology (POSTECH), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Jet Propulsion Laboratory, California Institute of Technology (JPL), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), and École normale supérieure - Paris (ENS-PSL)

Subjects
Physics, [PHYS]Physics [physics], 010504 meteorology & atmospheric sciences, Continuum (design consultancy), Comet, Astronomy and Astrophysics, Astrophysics, Spatial distribution, 01 natural sciences, Outgassing, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], 0103 physical sciences, Nadir, Sublimation (phase transition), Variation (astronomy), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Line (formation)
Abstract

International audience; Aims: Using spectroscopic and continuum data measured by the MIRO instrument on board Rosetta of comet 67P/Churyumov-Gerasimenko, it is possible to derive and track the change in the water production rate, to learn how the outgassing evolves with heliocentric distance. The MIRO data are well suited to investigate the evolution of 67P, in unprecedented spatial and temporal detail. Methods: To obtain estimates of the local effective Haser production rates we developed an efficient and reliable retrieval approach with precalculated lookup tables. We employed line area ratios (H216O/H218O) from pure nadir observations as the key variable, along with the Doppler shift velocity, and continuum temperature. This method was applied to the MIRO data from August 2014 until April 2016. Perihelion occurred on August 13, 2015 when the comet was 1.24 AU from the Sun. Results: During the perihelion approach, the water production rates increased by an order of magnitude, and from the observations, the derived maximum for a single observation on August 29, 2015 is (1.42 ± 0.51) ×1028. Modeling the data indicates that there is an offset in the peak outgassing, occurring 34 ± 10 days after perihelion. During the pre-perihelion phase, the production rate changes with heliocentric distance as rh-3.8±0.2; during post-perihelion, the dependence is rh-4.3±0.2. The comet is calculated to have lost 0.12 ± 0.06 % of its mass during the perihelion passage, considering only water ice sublimation. Additionally, this method provides well sampled data to determine the spatial distribution of outgassing versus heliocentric distance. The time evolution is definitely not uniform across the surface. Pre- and post-perihelion, the surface temperature on the southern hemisphere changes rapidly, as does the sublimation rate with an exponent of -6. There is a strong latitudinal dependence on the rh exponent with significant variation between northern and southern hemispheres, and so the average over the comet surface may only be of limited importance. We present more detailed regional variation in the outgassing, demonstrating that the highest derived production rates originate from the Wosret, Neith and Bes regions during perihelion.

Published
2017

6. Middle atmosphere polar warmings on Mars: Simulations and study on the validation with sub-millimeter observations

Author

Christopher Jarchow, Alexander S. Medvedev, and Paul Hartogh

Subjects
Astronomy and Astrophysics, Atmosphere of Mars, Mars Exploration Program, Atmospheric sciences, Atmosphere, Eddy, Space and Planetary Science, Physics::Space Physics, Radiative transfer, Polar, Astrophysics::Earth and Planetary Astrophysics, Hadley cell, Adiabatic process, Physics::Atmospheric and Oceanic Physics, Geology
Abstract

Temperature inversions and the warmings over the winter poles in the Martian atmosphere occur due to the adiabatic heating associated with the downward branch of the Hadley circulation. We present results of simulations with a recently developed GCM which suggest that the warmings are the manifestations of the global meridional transport, and are strongly related to atmospheric eddies (planetary waves and tides). To date, sets of data required for the validation of the predicted warmings and the corresponding circulation patterns do not extend far enough into the middle atmosphere of Mars. This motivated our radiative and retrieval simulations to demonstrate that sub-millimeter observations can provide the required fields to validate and constrain the GCM results.

Published
2007

7. On the winter anomaly of the night-to-day ratio of ozone in the middle to upper mesosphere in middle to high latitudes

Author

Mykhaylo Grygalashvyly, Christopher Jarchow, Paul Hartogh, G. R. Sonnemann, and Uwe Berger

Subjects
Atmospheric Science, Daytime, Ozone, Solar zenith angle, Aerospace Engineering, Astronomy and Astrophysics, Sudden stratospheric warming, Sunset, Atmospheric sciences, Mesosphere, Atmosphere, chemistry.chemical_compound, Geophysics, chemistry, Space and Planetary Science, Middle latitudes, General Earth and Planetary Sciences
Abstract

Long-term measurements of ozone by means of the microwave technique performed at Lindau (51.66°N, 10.13°E), Germany, revealed a winter anomaly of the night-to-day ratio (NDR) which is more clearly pronounced as the so-called tertiary nighttime ozone maximum. The domain of occurrence also differs somewhat from that of the nighttime ozone enhancement. The maximum winter-to-summer ratio amounts to a value of two to three in 70 km height. The annual variation of the NDR is modulated by oscillations of planetary time scale. 3D-calculations on the basis of the advanced GCM LIMA essentially reflect the observations but also show some typical differences which probably result from a somewhat too humid model atmosphere in middle latitudes. We analyzed the most important impacts on the middle mesospheric ozone. The strongest impacts are connected with the annual variation of water vapor and the so-called Doppler-Sonnemann effect considering the influence of the zonal wind on the chemistry due to the fact that ozone is subjected to an effective dissociation longer than molecular oxygen for an increasing solar zenith angle. Because of that the net odd oxygen production decreases faster than the formation of atomic oxygen from ozone which is involved in an odd oxygen destructing catalytic cycle. A shortening of the time of sunset by a west wind regime increases the nighttime ozone level relatively, whereas the daytime ozone is less influenced by the zonal wind in the domain considered.

Published
2007

8. The EChO science case

Author

Giovanna Tinetti, Pierre Drossart, Paul Eccleston, Paul Hartogh, Kate Isaak, Martin Linder, Christophe Lovis, Giusi Micela, Marc Ollivier, Ludovic Puig, Ignasi Ribas, Ignas Snellen, Bruce Swinyard, France Allard, Joanna Barstow, James Cho, Athena Coustenis, Charles Cockell, Alexandre Correia, Leen Decin, Remco de Kok, Pieter Deroo, Therese Encrenaz, Francois Forget, Alistair Glasse, Caitlin Griffith, Tristan Guillot, Tommi Koskinen, Helmut Lammer, Jeremy Leconte, Pierre Maxted, Ingo Mueller-Wodarg, Richard Nelson, Chris North, Enric Pallé, Isabella Pagano, Guseppe Piccioni, David Pinfield, Franck Selsis, Alessandro Sozzetti, Lars Stixrude, Jonathan Tennyson, Diego Turrini, Mariarosa Zapatero-Osorio, Jean-Philippe Beaulieu, Denis Grodent, Manuel Guedel, David Luz, Hans Ulrik Nørgaard-Nielsen, Tom Ray, Hans Rickman, Avri Selig, Mark Swain, Marek Banaszkiewicz, Mike Barlow, Neil Bowles, Graziella Branduardi-Raymont, Vincent Coudé du Foresto, Jean-Claude Gerard, Laurent Gizon, Allan Hornstrup, Christopher Jarchow, Franz Kerschbaum, Géza Kovacs, Pierre-Olivier Lagage, Tanya Lim, Mercedes Lopez-Morales, Giuseppe Malaguti, Emanuele Pace, Enzo Pascale, Bart Vandenbussche, Gillian Wright, Gonzalo Ramos Zapata, Alberto Adriani, Ruymán Azzollini, Ana Balado, Ian Bryson, Raymond Burston, Josep Colomé, Martin Crook, Anna Di Giorgio, Matt Griffin, Ruud Hoogeveen, Roland Ottensamer, Ranah Irshad, Kevin Middleton, Gianluca Morgante, Frederic Pinsard, Mirek Rataj, Jean-Michel Reess, Giorgio Savini, Jan-Rutger Schrader, Richard Stamper, Berend Winter, L. Abe, M. Abreu, N. Achilleos, P. Ade, V. Adybekian, L. Affer, C. Agnor, M. Agundez, C. Alard, J. Alcala, C. Allende Prieto, F. J. Alonso Floriano, F. Altieri, C. A. Alvarez Iglesias, P. Amado, A. Andersen, A. Aylward, C. Baffa, G. Bakos, P. Ballerini, M. Banaszkiewicz, R. J. Barber, D. Barrado, E. J. Barton, V. Batista, G. Bellucci, J. A. Belmonte Avilés, D. Berry, B. Bézard, D. Biondi, M. Błęcka, I. Boisse, B. Bonfond, P. Bordé, P. Börner, H. Bouy, L. Brown, L. Buchhave, J. Budaj, A. Bulgarelli, M. Burleigh, A. Cabral, M. T. Capria, A. Cassan, C. Cavarroc, C. Cecchi-Pestellini, R. Cerulli, J. Chadney, S. Chamberlain, N. Christian Jessen, A. Ciaravella, A. Claret, R. Claudi, A. Coates, R. Cole, A. Collur, D. Cordier, E. Covino, C. Danielski, M. Damasso, H. J. Deeg, E. Delgado-Mena, C. Del Vecchio, O. Demangeon, A. De Sio, J. De Wit, M. Dobrijévi, P. Doel, C. Dominic, E. Dorfi, S. Eales, C. Eiroa, M. Espinoza Contreras, M. Esposito, V. Eymet, N. Fabrizio, M. Fernández, B. Femenía Castella, P. Figueira, G. Filacchione, L. Fletcher, M. Focardi, S. Fossey, P. Fouqué, J. Frith, M. Galand, L. Gambicorti, P. Gaulme, R. J. García López, A. Garcia-Piquer, W. Gear, J. -C. Gerard, L. Gesa, E. Giani, F. Gianotti, M. Gillon, E. Giro, M. Giuranna, H. Gomez, I. Gomez-Leal, J. Gonzalez Hernandez, B. GonzÁlez Merino, R. Graczyk, D. Grassi, J. Guardia, P. Guio, J. Gustin, P. Hargrave, J. Haigh, E. Hébrard, U. Heiter, R. L. Heredero, E. Herrero, F. Hersant, D. Heyrovsky, M. Hollis, B. Hubert, R. Hueso, G. Israelian, N. Iro, P. Irwin, S. Jacquemoud, G. Jones, H. Jones, K. Justtanont, T. Kehoe, F. Kerschbaum, E. Kerins, P. Kervell, D. Kipping, T. Koskinen, N. Krupp, O. Lahav, B. Laken, N. Lanza, E. Lellouch, G. Leto, J. Licandro Goldaracena, C. Lithgow Bertelloni, S. J. Liu, U. Lo Cicero, N. Lodieu, P. Lognonné, M. Lopez Puertas, M. A. Lopez Valverde, I. Lundgaard Rasmussen, A. Luntzer, P. Machado, C. Mac Tavish, A. Maggio, J. P. Maillard, W. Magnes, J. Maldonado, U. Mall, J. B. Marquette, P. Mauskopf, F. Massi, A. S. Maurin, A. Medvedev, C. Michaut, P. Miles Paez, M. Montalto, P. Montañés Rodríguez, M. Monteiro, D. Montes, H. Morais, J. C. Morale, M. Morales-Calderón, G. Morello, A. Moro Martín, J. Moses, A. Moya Bedon, F. Murgas Alcaino, E. Oliva, G. Orton, F. Palla, M. Pancrazzi, E. Pantin, V. Parmentier, H. Parviainen, Y. Pena Ramirez, J. Peralta, S. Perez-Hoyos, R. Petrov, S. Pezzuto, R. Pietrzak, E. Pilat-Lohinger, N. Piskunov, R. Prinja, L. Prisinzano, I. Polichtchouk, E. Poretti, A. Radioti, A. Ramos, T. Rank-Luftinger, P. Read, K. Readorn, R. Rebolo Lopez, J. Rebordao, M. Rengel, L. Rezac, M. Rocchetto, F. Rodler, J. Sanchez Bejar, A. Sanchez Lavega, E. Sanroma, N. Santos, J. Sanz Forcada, G. Scandariato, F.- X. Schmider, A. Scholz, S. Scuderi, J. Sethenadh, S. Shore, A. Showman, B. Sicardy, P. Sitek, A. Smith, L. Soret, S. Sousa, A. Stiepen, M. Stolarski, G. Strazzulla, H. M. Tabernero, P. Tanga, M. Tecsa, J. Temple, L. Terenzi, M. Tessenyi, L. Testi, S. Thompson, H. Thrastarson, B. W. Tingley, M. Trifoglio, J. Martin Torres, A. Tozzi, D. Turrini, R. Varley, F. Vakili, M. de Val-Borro, M. L. Valdivieso, O. Venot, E. Villaver, S. Vinatier, S. Viti, I. Waldmann, D. Waltham, D. Ward-Thompson, R. Waters, C. Watkins, D. Watson, P. Wawer, A. Wawrzaszk, G. White, T. Widemann, W. Winek, T. Wi.niowski, R. Yelle, Y. Yung, and S. N. Yurchenko

Subjects
13. Climate action, 7. Clean energy
Published
2015

9. Distribution of water around the nucleus of comet 67P/Churyumov-Gerasimenko at 3.4 AU from the Sun as seen by the MIRO instrument on Rosetta

Author

Wing-Huen Ip, F. P. Schloerb, Ladislav Rezac, Pierre Encrenaz, Christopher Jarchow, M. Hofstadter, Dominique Bockelée-Morvan, Jacques Crovisier, Seungwon Lee, C. Leyrat, Emmanuel Lellouch, Mathieu Choukroun, Paul Hartogh, Samuel Gulkis, N. Biver, P. von Allmen, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Institute of Space Science [Taiwan], National Central University [Taiwan] (NCU), Northern Research Station, Forestry Commission, Human Computer Technology Laboratory (HCTLab), Universidad Autónoma de Madrid (UAM), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung (MPS), Universidad Autonoma de Madrid (UAM), and École normale supérieure - Paris (ENS Paris)

Subjects
Physics, [PHYS]Physics [physics], Comet, Solid angle, Astronomy, Astronomy and Astrophysics, Coma (optics), Astrophysics, Rotation, law.invention, Wavelength, Outgassing, Orbiter, medicine.anatomical_structure, Space and Planetary Science, law, [SDU]Sciences of the Universe [physics], medicine, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Nucleus, ComputingMilieux_MISCELLANEOUS
Abstract

The Microwave Instrument on the Rosetta Orbiter (MIRO) has been observing the coma of comet 67P/Churyumov-Gerasimenko almost continuously since June 2014 at wavelengths near 0.53 mm. We present here a map of the water column density in the inner coma (within 3 km from nucleus center) when the comet was at 3.4 AU from the Sun. Based on the analysis of the H2 16 O and H2 18 O (110-101) lines, we find that the column density can vary by two orders of magnitude in this region. The highest column density is observed in a narrow region on the dayside, close to the neck and north pole rotation axis of the nucleus, while the lowest column density is seen against the nightside of the nucleus where outgassing seems to be very low. We estimate that the outgassing pattern can be represented by a Gaussian distribution in a solid angle with FWHM ≈ 80°.

Published
2015

10. Cometary science. Subsurface properties and early activity of comet 67P/Churyumov-Gerasimenko

Author

Samuel, Gulkis, Mark, Allen, Paul, von Allmen, Gerard, Beaudin, Nicolas, Biver, Dominique, Bockelée-Morvan, Mathieu, Choukroun, Jacques, Crovisier, Björn J R, Davidsson, Pierre, Encrenaz, Therese, Encrenaz, Margaret, Frerking, Paul, Hartogh, Mark, Hofstadter, Wing-Huen, Ip, Michael, Janssen, Christopher, Jarchow, Stephen, Keihm, Seungwon, Lee, Emmanuel, Lellouch, Cedric, Leyrat, Ladislav, Rezac, F Peter, Schloerb, and Thomas, Spilker

Abstract

Heat transport and ice sublimation in comets are interrelated processes reflecting properties acquired at the time of formation and during subsequent evolution. The Microwave Instrument on the Rosetta Orbiter (MIRO) acquired maps of the subsurface temperature of comet 67P/Churyumov-Gerasimenko, at 1.6 mm and 0.5 mm wavelengths, and spectra of water vapor. The total H2O production rate varied from 0.3 kg s(-1) in early June 2014 to 1.2 kg s(-1) in late August and showed periodic variations related to nucleus rotation and shape. Water outgassing was localized to the "neck" region of the comet. Subsurface temperatures showed seasonal and diurnal variations, which indicated that the submillimeter radiation originated at depths comparable to the diurnal thermal skin depth. A low thermal inertia (~10 to 50 J K(-1) m(-2) s(-0.5)), consistent with a thermally insulating powdered surface, is inferred.

Published
2015

11. Subsurface properties and early activity of comet 67P/Churyumov-Gerasimenko

Author

Christopher Jarchow, Seungwon Lee, Stephen Keihm, F. Peter Schloerb, Dominique Bockelée-Morvan, C. Leyrat, Michael Janssen, Samuel Gulkis, Pierre Encrenaz, Jacques Crovisier, Björn Davidsson, Emmanuel Lellouch, Mark Allen, Thérèse Encrenaz, Ladislav Rezac, Nicolas Biver, Thomas R. Spilker, Mathieu Choukroun, Paul Hartogh, Gerard Beaudin, Margaret A. Frerking, Paul von Allmen, Mark Hofstadter, Wing-Huen Ip, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and École normale supérieure - Paris (ENS Paris)

Subjects
[PHYS]Physics [physics], Multidisciplinary, Chemistry, Comet, Atmospheric sciences, Spectral line, law.invention, Wavelength, Outgassing, Orbiter, 13. Climate action, law, Thermal, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Microwave, Water vapor, ComputingMilieux_MISCELLANEOUS
Abstract

Heat transport and ice sublimation in comets are interrelated processes reflecting properties acquired at the time of formation and during subsequent evolution. The Microwave Instrument on the Rosetta Orbiter (MIRO) acquired maps of the subsurface temperature of comet 67P/Churyumov-Gerasimenko, at 1.6 mm and 0.5 mm wavelengths, and spectra of water vapor. The total H 2 O production rate varied from 0.3 kg s –1 in early June 2014 to 1.2 kg s –1 in late August and showed periodic variations related to nucleus rotation and shape. Water outgassing was localized to the “neck” region of the comet. Subsurface temperatures showed seasonal and diurnal variations, which indicated that the submillimeter radiation originated at depths comparable to the diurnal thermal skin depth. A low thermal inertia (~10 to 50 J K –1 m –2 s –0.5 ), consistent with a thermally insulating powdered surface, is inferred.

Published
2015

12. Behavior of mesospheric ozone under nearly polar night conditions

Author

G. R. Sonnemann, Paul Hartogh, Christopher Jarchow, and Mykhaylo Grygalashvyly

Subjects
Atmospheric Science, Ozone, Polar night, Chemistry, Terminator (solar), Photodissociation, Aerospace Engineering, Astronomy and Astrophysics, Atmospheric sciences, Mesosphere, chemistry.chemical_compound, Geophysics, Space and Planetary Science, Ozone layer, Mesopause, Mixing ratio, General Earth and Planetary Sciences
Abstract

The spatio-temporal behavior of the ozone mixing ratio in the upper mesosphere/mesopause region under nearly polar night conditions is one phenomenon not completely understood and reproduced by models thus far. On the basis of a sophisticated 3D-model of the dynamics and chemistry of the middle atmosphere (0–150 km) particularly designed to investigate the extended mesopause region, we examine the spatio-temporal structure of this phenomenon and discuss it in terms of chemistry. The most marked feature is a pronounced ozone maximum around 72 km, also called the tertiary ozone maximum, and a large decrease of the mixing ratios around 80 km. This feature was also found by means of ground-based microwave measurements in middle latitude at Lindau (51.66 °N) and high latitude at ALOMAR (69.29 °N) during the night in the winter season. It was, however, absent during the daytime hours. The calculations brought evidence that the enhanced ozone values occur in a latitudinal band close to the polar night terminator. It is confined both to a height range approximately between 66 and 77 km and to a certain latitudinal range which alters with the season according to the change of the polar night terminator. For a constant latitude there are two annual maxima of the ozone mixing ratio that occur nearly symmetrically about the winter solstice. These maxima are more widely separated at higher latitudes. The theoretical analysis of this phenomenon showed that while ozone is formed under nearly grazing incidence conditions the radiation that dissociates water vapor is almost completely absorbed. This means that the formation of hydrogen radicals that destroy odd oxygen is significantly reduced but there is still some atomic oxygen production that permits ozone formation during the short twilight periods close to the polar night terminator. The loss of the accumulated ozone takes place partly through the Chapman reactions of a pure oxygen system and partly through catalytic reactions, including HO x radicals that result from O( 1 D) oxidation of the even hydrogens H 2 and H 2 O and a residual photolysis of H 2 O. The O( 1 D) oxidation is important because the ozone dissociation rate is only slightly reduced for grazing incidence conditions in that region. Within the region of the large ozone decrease near 80 km the chemistry is marked by a steady increase of atomic hydrogen entailing a decrease of ozone and HO 2 . The poleward directed meridional wind also transports ozone into the polar night.

Published
2006

13. Herschel observations of gas and dust in comet C/2006 W3 (Christensen) at 5 AU from the Sun

Author

Miriam Rengel, Jean Manfroid, C. Waelkens, Emmanuel Jehin, D. Teyssier, Th. de Graauw, L. M. Lara, Christopher Jarchow, Paul Hartogh, Ladislav Rezac, Michael Küppers, Dominique Bockelée-Morvan, Damien Hutsemekers, M. de Val-Borro, M. R. Kidger, C. Opitom, Slawomira Szutowicz, Dariusz C. Lis, N. Biver, B. M. Swinyard, B. Vandenbussche, J. Crovisier, Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, Max Planck Institute for Aeronomy (MPAe), foreign laboratories (FL), CERN [Genève], Instituto de Astrofisica de Canarias (IAC), Department of Physiology and Biochemistry of Animal Nutrition, Spanish National Research Council (CSIC), Instituut voor Sterrenkunde [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), and Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS)

Subjects
Physics, Earth and Planetary Astrophysics (astro-ph.EP), [PHYS]Physics [physics], Subsolar point, individual: C/2006 W3 (Christensen) [comets], FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Thermal emission, planetary systems [submillimeter], Spectral line, Blueshift, photometric [techniques], Outgassing, 13. Climate action, Space and Planetary Science, Sublimation (phase transition), spectroscopic [techniques], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Hyperfine structure, Order of magnitude, ComputingMilieux_MISCELLANEOUS, Astrophysics - Earth and Planetary Astrophysics
Abstract

We aimed to measure the H2O and dust production rates in C/2006 W3 (Christensen) with the Herschel Space Observatory at a heliocentric distance of ~ 5 AU. We have searched for emission in the H2O and NH3 ground-state rotational transitions at 557 GHz and 572 GHz, simultaneously, with HIFI onboard Herschel on UT 1.5 September 2010. Photometric observations of the dust coma in the 70 and 160 {\mu}m channels were acquired with the PACS instrument on UT 26.5 August 2010. A tentative 4-{\sigma} H2O line emission feature was found in the spectra obtained with the HIFI wide-band and high-resolution spectrometers, from which we derive a water production rate of $2.0(5) \times 10^{27}$ molec. s$^{-1}$. A 3-{\sigma} upper limit for the ammonia production rate of, Comment: 13 pages, 9 figures

Published
2014

14. New determination of the HCN profile in the stratosphere of Neptune from millimeter-wave spectroscopy

Author

Paul Hartogh, Miriam Rengel, Michel Dobrijevic, Thibault Cavalié, Christopher Jarchow, Ladislav Rezac, M. de Val-Borro, Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, SSE 2014, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), and Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)

Subjects
Physics, planets and satellites: atmospheres, 010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], planets and satellites: composition, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astronomy and Astrophysics, Context (language use), submillimeter: planetary systems, Astrophysics, 01 natural sciences, Spectral line, Atmospheric radiative transfer codes, 13. Climate action, Space and Planetary Science, Neptune, 0103 physical sciences, Millimeter, Spectral resolution, Spectroscopy, 010303 astronomy & astrophysics, Stratosphere, 0105 earth and related environmental sciences
Abstract

International audience; Context. Periodic monitoring of the atmospheric composition is the cornerstone of planetary atmospheric science. It reveals temporal and/or spatial variations. Ground-based observations of rotational lines from the (sub-)millimeter wavelength range is a suitable method to obtain the mean HCN profile in Neptune's startosphere. Aims: We aimed at deriving new constraints on the disk-averaged HCN stratospheric profile and abundance. The 14-year gap between the last published observations and ours of HCN in Neptune can be used to constrain any possible time variation of this main nitrogen-bearing molecule at the probed altitudes. This temporal variation could additionally reveal, albeit indirectly, the dominant process responsible for the origin of the nitrogen compoundsin the stratosphere of Neptune. Methods: Spectra of the HCN (J = 3-2) line at 265.886 GHz were obtained with the 1.3 mm receiver of the Submillimeter Telescope (SMT) at the Arizona Radio Observatory (ARO) using several backends simultaneously. The spectral resolution of the analyzed datasets was 1 MHz and 250 kHz, providing a signal-to-noise ratio of 20 and 11, respectively. Pre-processing of the spectra involved baseline removal and de-noising using the empirical mode decomposition technique. The spectra were then inverted using a line-by-line radiative transfer model to obtain the vertical profile of HCN between 2 mbar to 10 μbar and derive the column density. Results: The retrieved mean stratospheric HCN mole fraction is (1.3 ± 0.6) × 10-9 above 0.5 millibar, corresponding to a column density of 2.2 × 1014 molecules cm-2. The data are consistent with a pronounced HCN decrease below the 0.6 mbar level, which agrees with previous findings.

Published
2014

15. [Untitled]

Author

R. N. Martin, Paul Hartogh, Joseph P. McMullin, W. L. Peters, Mark Hofstadter, and Christopher Jarchow

Subjects
Physics, Planetary science, Space and Planetary Science, Short Term Variability, Comet, Earth and Planetary Sciences (miscellaneous), Astronomy, Astronomy and Astrophysics, Coma (optics), Spatial variability, sense organs, Comet Hale–Bopp
Abstract

We observed submillimeter lines of H2CO and HCN in comet Hale-Bopp near perihelion. One of our goals was to search for short term variability. Our observations are suggestive, but not conclusive, of temporal and/or spatial changes in the coma's HCN/H2CO abundance ratio of ∼25%. If due to spatial variability, the ratio on the sunward side of the coma is enhanced over other regions. If due to temporal variability, we find the bulk ratio in the coma changed in less than 16 hours.

Published
1997

16. Spatial distribution of water in the stratosphere of Jupiter from Herschel HIFI and PACS observations

Author

G. S. Orton, Christopher Jarchow, Michel Dobrijevic, Emmanuel Lellouch, F. Billebaud, Hideo Sagawa, M. de Val-Borro, Helmut Feuchtgruber, R. Moreno, A. Gonzalez, Thomas K. Greathouse, Paul Hartogh, Thibault Cavalié, L. M. Lara, SSE 2013, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), foreign laboratories (FL), CERN [Genève], Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Southwest Research Institute [San Antonio] (SwRI), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), and Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS)

Subjects
010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Comet, Infrared telescope, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Context (language use), Astrophysics, planets and satellites: individual: Jupiter, 01 natural sciences, law.invention, Telescope, Jupiter, law, 0103 physical sciences, 010303 astronomy & astrophysics, Stratosphere, 0105 earth and related environmental sciences, Physics, planets and satellites: atmospheres, Astronomy, Astronomy and Astrophysics, submillimeter: planetary systems, 13. Climate action, Space and Planetary Science, Planetary mass, Jupiter mass
Abstract

International audience; Context. In the past 15 years, several studies suggested that water in the stratosphere of Jupiter originated from the Shoemaker-Levy 9 (SL9) comet impacts in July 1994, but a direct proof was missing. Only a very sensitive instrument observing with high spectral/spatial resolution can help to solve this problem. This is the case of the Herschel Space Observatory, which is the first telescope capable of mapping water in Jupiter's stratosphere. Aims: We observed the spatial distribution of the water emission in Jupiter's stratosphere with the Heterodyne Instrument for the Far Infrared (HIFI) and the Photodetector Array Camera and Spectrometer (PACS) onboard Herschel to constrain its origin. In parallel, we monitored Jupiter's stratospheric temperature with the NASA Infrared Telescope Facility (IRTF) to separate temperature from water variability. Methods: We obtained a 25-point map of the 1669.9 GHz water line with HIFI in July 2010 and several maps with PACS in October 2009 and December 2010. The 2010 PACS map is a 400-point raster of the water 66.4 μm emission. Additionally, we mapped the methane ν4 band emission to constrain the stratospheric temperature in Jupiter in the same periods with the IRTF. Results: Water is found to be restricted to pressures lower than 2 mbar. Its column density decreases by a factor of 2-3 between southern and northern latitudes, consistently between the HIFI and the PACS 66.4 μm maps. We infer that an emission maximum seen around 15 °S is caused by a warm stratospheric belt detected in the IRTF data. Conclusions: Latitudinal temperature variability cannot explain the global north-south asymmetry in the water maps. From the latitudinal and vertical distributions of water in Jupiter's stratosphere, we rule out interplanetary dust particles as its main source. Furthermore, we demonstrate that Jupiter's stratospheric water was delivered by the SL9 comet and that more than 95% of the observed water comes from the comet according to our models. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.Figures 1 and 3 are available in electronic form at http://www.aanda.org

Published
2013

17. First submillimeter observation of CO in the stratosphere of Uranus

Author

Christopher Jarchow, Leigh Fletcher, Paul Hartogh, T. Encrenaz, E. Lellouch, T. Cavalié, Franck Hersant, R. Moreno, G. S. Orton, O. Venot, F. Selsis, SSE 2014, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Center for Medical Imaging Science and Visualization - Dept. of Medical and Health Sciences, Linköping University (LIU), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, FORMATION STELLAIRE 2014, Department of Atmospheric, Oceanic and Planetary Physics [Oxford] (AOPP), University of Oxford [Oxford], Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), University of Oxford, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux ( L3AB ), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Observatoire aquitain des sciences de l'univers ( OASU ), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Laboratoire d'Astrophysique de Bordeaux [Pessac] ( LAB ), Université de Bordeaux ( UB ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Bordeaux ( UB ), Linköping University ( LIU ), Max-Planck-Institut für Sonnensystemforschung ( MPS ), Laboratoire d'études spatiales et d'instrumentation en astrophysique ( LESIA ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ), and Department of Atmospheric, Oceanic and Planetary Physics [Oxford] ( AOPP )

Subjects
010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, 7. Clean energy, Troposphere, Jupiter, Neptune, Planet, 0103 physical sciences, Atmosphere of Uranus, 010303 astronomy & astrophysics, Stratosphere, 0105 earth and related environmental sciences, Physics, planets and satellites: atmospheres, Earth and Planetary Astrophysics (astro-ph.EP), Uranus, Astronomy and Astrophysics, submillimeter: planetary systems, planetary systems [submillimeter], atmospheres [planets and satellites], [ SDU.ASTR.EP ] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], planets and satellites: individual: Uranus, [ PHYS.ASTR.EP ] Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], 13. Climate action, Space and Planetary Science, individual: Uranus [planets and satellites], Astrophysics - Earth and Planetary Astrophysics
Abstract

Context. Carbon monoxide (CO) has been detected in all Giant Planets and its origin is both internal and external in Jupiter and Neptune. Despite its first detection in Uranus a decade ago, the magnitude of its internal and external sources remains unconstrained. Aims. We targeted CO lines in Uranus in the submillimeter range to constrain its origin. Methods. We recorded disk-averaged spectra of Uranus with a very high spectral resolution at the frequencies of CO rotational lines in the submillimeter range in 2011-2012. We used empirical and diffusion models of the atmosphere of Uranus to constrain the origin of CO. We also used a thermochemical model of its troposphere to derive an upper limit on the O/H ratio in the deep atmosphere of Uranus. Results. We have detected the CO(8-7) rotational line for the first time, with Herschel-HIFI. Both empirical and diffusion model results show that CO has an external origin. An empirical profile in which CO is constant above the 100mbar level with a mole fraction of 7.1-9.0E-9 (depending on the adopted stratospheric thermal structure) reproduces the data. Sporadic and steady source models cannot be differentiated with our data. Taking Teanby & Irwin's internal source model upper limit of a mole fraction of 2.1E-9 [Teanby & Irwin 2013. ApJ, 775, L49], the deep O/H ratio of Uranus is lower than 500 times solar according to our thermochemical computations. Conclusions. Our work shows that the average mole fraction of CO decreases from the stratosphere to the troposphere and thus strongly advocates for an external source of CO in Uranus. Photochemical modeling of oxygen species in the atmosphere of Uranus and more sensitive observations are needed to reveal the nature of the external source., 7 pages, 3 figures, 3 tables. Accepted for publication in A&A 7th November 2013

Published
2013
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18. Investigations of the Solar Influence on Middle Atmospheric Water Vapour and Ozone During the Last Solar Cycle—Analysis of the MPS Data Set

Author

Kristoffer Hallgren, Christopher Jarchow, and Paul Hartogh

Subjects
Daytime, Stratopause, Middle latitudes, Solar zenith angle, Solstice, Environmental science, Atmospheric sciences, Latitude, Mesosphere, Solar cycle
Abstract

The MPS water vapour and ozone data set was gained with ground-based microwave heterodyne spectrometers operating since mid of the nineties of the last century at two locations: at MPS at mid latitude in Katlenburg-Lindau (51.66°N, 10.13°E) in Germany and at ALOMAR in polar latitude at (69.29°N, 16.03°E) in Northern Norway. The water vapour observations show a pronounced year-to-year variability with annual maxima in summer and minima in winter related to the Lyman-α radiation. In winter we found an anti-correlation of upper mesospheric water vapour with the solar activity. After winter solstice the mesospheric water vapour concentration is strongly influenced by sudden stratospheric warmings (SSWs) appearing more frequently during high solar activity. In the stratopause and lower mesosphere region we find a positive correlation with solar activity during the whole year. Ozone also shows a strong (but different) annual pattern: we find a late summer maximum in the middle and lower mesosphere which is shifted into autumn and winter in the stratopause region, and a distinct nighttime maximum around 72 km during the winter season, whereas no annual maximum occurs there during daytime. A clear annual asymmetry of the nighttime ozone distribution exists in this domain, marked by a decline of the mean ozone values in January/February and an increase to the subsidiary annual maximum a few kilometres higher in March/April. These asymmetric variations result from the asymmetric occurrence rate of SSWs with maxima after winter solstice and the asymmetric annual variation of water vapour with minima around spring equinox.

Published
2013

20. In-orbit performance of Herschel-HIFI

Author

N. Whyborn, Per Bjerkeli, Pieter R. Roelfsema, Dominicus Kester, L. Dubbeldam, Q. Xie, Claudia Comito, Z. Nagy, A. Marston, R. Moreno, J. Rector, C. Gal, M. H. D. van der Wiel, M. Akyilmaz, Christian Leinz, Michael Olberg, Miriam Rengel, Mihkel Kama, T. Klein, D. R. Higgins, Tomasz S. Kaminski, Yoko Okada, E. Sánchez-Suárez, S. Pacheco, G. de Lange, J. Stutzki, I. M. Avruch, W. Salomons, R. Assendorp, Tom Bell, R. Shipman, W. Nowosielski, O. Coeur-Joly, Volker Ossenkopf, Adwin Boogert, C. Kramer, W. M. Laauwen, S. D. Lord, J. C. Pearson, M. Marseille, Rudolf Schieder, Piotr Orleanski, J. Braine, C. K. Wafelbakker, D. Rabois, C. McCoey, Marco Soldati, A. de Jonge, L. Ravera, Charlotte Vastel, Christopher Jarchow, S. Wang, F. Schlöder, F. Flederus, W. Luinge, Pieter Dieleman, Umut A. Yildiz, Robin Lombaert, Christophe Risacher, Emmanuel Caux, Nathan R. Crockett, B. Delforge, M. Melchior, M. De Luca, Willem Jellema, Fabrice Herpin, N. Biver, A. Lorenzani, Thomas G. Phillips, B. Thomas, Patrick W. Morris, K. Wildeman, E. De Beck, P. Zaal, Hideo Sagawa, Jesús Martín-Pintado, K. Edwards, R. Huisman, Colin Borys, M. Caris, Alexander G. G. M. Tielens, Michel Fich, Jacob Kooi, Th. de Graauw, M. Michalska, Z. Makai, M. Xilouris, A. Hoac, Frank Helmich, Thibault Cavalié, F. Schmülling, Bengt Larsson, D. A. Beintema, A. M. di Giorgio, José Cernicharo, Holger S. P. Müller, Bertrand Lefloch, D. Teyssier, Pierre Hily-Blant, SRON Netherlands Institute for Space Research (SRON), Infrared Processing and Analysis Center (IPAC), California Institute of Technology (CALTECH), Onsala Space Observatory, Chalmers University of Technology [Göteborg], foreign laboratories (FL), CERN [Genève], ESO, European Southern Observatory (ESO), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), FORMATION STELLAIRE 2012, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), CNRS INSU, UMR 5187, F-31028 Toulouse 4, France, UMR 5187 Toulouse, Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Max Planck Institute for Radio Astronomy, Max-Planck-Institut für Radioastronomie (MPIFR), Instituto de RadioAstronomía Milimétrica (IRAM), Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, I. Physikalisches Institut [Köln], Universität zu Köln = University of Cologne, SSE 2012, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Department of Astronomy [Ann Arbor], University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Laboratoire Univers et Théories (LUTH (UMR_8102)), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA, CALTECH, Ctr Infrared Proc & Anal, Pasadena, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid 28850, Spain, Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung (MPS), Univ Cologne, Inst Phys 1, D-50937 Cologne, Germany, Univ Cologne, Inst Phys 1, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), École normale supérieure - Paris (ENS Paris), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Universität zu Köln, Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Kapteyn Astronomical Institute, Astronomy, Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Heterodyne, Physics, [PHYS]Physics [physics], 010504 meteorology & atmospheric sciences, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Instrumentation, Astrophysics::Instrumentation and Methods for Astrophysics, ASTRONOMY, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, 7. Clean energy, Methods observational, Space and Planetary Science, 0103 physical sciences, Orbit (dynamics), Calibration, methods: observational, space vehicles: instruments, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Remote sensing, instrumentation: spectrographs
Abstract

International audience; Aims: In this paper the calibration and in-orbit performance of the Heterodyne Instrument for the Far-Infrared (HIFI) is described. Methods: The calibration of HIFI is based on a combination of ground and in-flight tests. Dedicated ground tests to determine those instrument parameters that can only be measured accurately using controlled laboratory stimuli were carried out in the instrument level test (ILT) campaign. Special in-flight tests during the commissioning phase (CoP) and performance verification (PV) allowed the determination of the remaining instrument parameters. The various instrument observing modes, as specified in astronomical observation templates (AOTs), were validated in parallel during PV by observing selected celestial sources. Results: The initial calibration and in-orbit performance of HIFI has been established. A first estimate of the calibration budget is given. The overall in-flight instrument performance agrees with the original specification. Issues remain at only a few frequencies. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Published
2012

21. Direct detection of the Enceladus water torus with Herschel

Author

M. Kidger, Dominique Bockelée-Morvan, Frank Helmich, J. Crovisier, Miriam Rengel, Paul Hartogh, R. Moreno, N. Biver, Emmanuel Lellouch, T. Cassidy, Christopher Jarchow, Thibault Cavalié, Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Max-Planck-Institut für Sonnensystemforschung (MPS), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1

Subjects
010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astrophysics, 01 natural sciences, 7. Clean energy, symbols.namesake, 0103 physical sciences, submillimetre: planetary system, STRATOSPHERE, Enceladus, Space research, CARBON-MONOXIDE, 010303 astronomy & astrophysics, Stratosphere, Physics::Atmospheric and Oceanic Physics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Physics, JUPITER, planets and satellites: individual: Saturn, ORIGIN, Astronomy, ASTRONOMY, Astronomy and Astrophysics, Torus, Scale height, PLUME, Gas torus, SATURNS ATMOSPHERE, Space and Planetary Science, Physics::Space Physics, symbols, VAPOR, Astrophysics::Earth and Planetary Astrophysics, Titan (rocket family), EMISSION, Water vapor, planets and satellites: individual: Enceladus, techniques: spectroscopic, SYSTEM
Abstract

International audience; Cryovolcanic activity near the south pole of Saturn's moon Enceladus produces plumes of H2O-dominated gases and ice particles, which escape and populate a torus-shaped cloud. Using submillimeter spectroscopy with Herschel, we report the direct detection of the Enceladus water vapor torus in four rotational lines of water at 557, 987, 1113, and 1670 GHz, and probe its physical conditions and structure. We determine line-of-sight H2O column densities of ~4 × 1013 cm-2 near the equatorial plane, with a ~50 000 km vertical scale height. The water torus appears to be rotationally cold (e.g. an excitation temperature of 16 K is measured for the 1113 GHz line) but dynamically excited, with non-Keplerian dispersion velocities of ~2 km s-1, and appears to be largely shaped by molecular collisions. From estimates of the influx rates of torus material into Saturn and Titan, we infer that Enceladus' activity is likely to be the ultimate source of water in the upper atmosphere of Saturn, but not in Titan's. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. HIFI has been designed and built by a consortium of institutes and university departments from across Europe, Canada and the United States under the leadership of SRON Netherlands Institute for Space Research, Groningen, The Netherlands and with major contributions from Germany, France and the US.Figures 4 and 5 are available in electronic form at http://www.aanda.org

Published
2011

23. Gas morphology and energetics at the surface of PDRs: New insights with Herschel observations of NGC 7023

Author

C. Joblin, M. Akyilmaz, Peter G. Martin, Emmanuel Caux, O. Siebertz, Rolf Güsten, Olivier Berné, F. Boulanger, Paul Hartogh, E. Steinmetz, F. F. S. van der Tak, B. Colin, Yoko Okada, S. Bruderer, P. Pilleri, Andrew I. Harris, J. Montillaud, Markus Röllig, Asunción Fuente, Juergen Stutzki, Robert Simon, Bhaswati Mookerjea, Maryvonne Gerin, J. R. Rizzo, Volker Ossenkopf, Arnold O. Benz, Javier R. Goicoechea, J. Le Bourlot, Thomas G. Phillips, S. D. Lord, H. W. Yorke, Christopher Jarchow, F. Le Petit, T. Klein, C. Dedes, D. Teyssier, Jesús Martín-Pintado, Cornelia E. Honingh, Carsten Kramer, Astronomy, Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Los Alamos National Laboratory (LANL), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Université de Franche-Comté (UFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Observatorio Astronómico Nacional (OAN), oan, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), European Space Astronomy Centre (ESAC), European Space Agency (ESA), Physikalisches Institut [Köln], Universität zu Köln, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Extraterrestrische Physik (MPE), Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Center for Astrophysics and Space Astronomy [Boulder] (CASA), University of Colorado [Boulder], Division for Submm Technologies, Max-Planck-Institut für Radioastronomie (MPIFR), CRUK Medical Oncology Unit, The Churchill Hospital, Instituto de RadioAstronomía Milimétrica (IRAM), Centre National de la Recherche Scientifique (CNRS), KOSMA, I. Physikalisches Institut, foreign laboratories (FL), CERN [Genève], Helmholtz zentrum für Schwerionenforschung GmbH (GSI), Laboratoire Electronique, Informatique et Image [UMR6306] (Le2i), Université de Bourgogne (UB)-École Nationale Supérieure d'Arts et Métiers (ENSAM), Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, CNRS INSU, UMR 5187, F-31028 Toulouse 4, France, UMR 5187 Toulouse, Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Arts et Métiers (ENSAM), and HESAM Université (HESAM)-HESAM Université (HESAM)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement

Subjects
Surface (mathematics), GRAINS, Field (physics), ISM: structure, Extinction (astronomy), Dust particles, FOS: Physical sciences, DUST, Astrophysics, PHOTODISSOCIATION REGIONS, 01 natural sciences, POLYCYCLIC AROMATIC-HYDROCARBONS, 0103 physical sciences, Transfer model, 010306 general physics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Line (formation), Physics, ISM: kinematics and dynamics, Nebula, SPECTROSCOPY, INTERSTELLAR-MEDIUM, Energetics, Astronomy and Astrophysics, NGC-7023, Astrophysics - Astrophysics of Galaxies, ISM: molecules, CLOUD, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), submillimeter: ISM, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], EMISSION
Abstract

We investigate the physics and chemistry of the gas and dust in dense photon-dominated regions (PDRs), along with their dependence on the illuminating UV field. Using Herschel-HIFI observations, we study the gas energetics in NGC 7023 in relation to the morphology of this nebula. NGC 7023 is the prototype of a PDR illuminated by a B2V star and is one of the key targets of Herschel. Our approach consists in determining the energetics of the region by combining the information carried by the mid-IR spectrum (extinction by classical grains, emission from very small dust particles) with that of the main gas coolant lines. In this letter, we discuss more specifically the intensity and line profile of the 158 micron (1901 GHz) [CII] line measured by HIFI and provide information on the emitting gas. We show that both the [CII] emission and the mid-IR emission from polycyclic aromatic hydrocarbons (PAHs) arise from the regions located in the transition zone between atomic and molecular gas. Using the Meudon PDR code and a simple transfer model, we find good agreement between the calculated and observed [CII] intensities. HIFI observations of NGC 7023 provide the opportunity to constrain the energetics at the surface of PDRs. Future work will include analysis of the main coolant line [OI] and use of a new PDR model that includes PAH-related species., Comment: Accepted for publication in Astronomy and Astrophysics Letters (Herschel HIFI special issue), 5 pages, 5 figures

Published
2010

24. A study of the distant activity of comet C/2006 W3 (Christensen) using Herschel and ground-based radio telescopes

Author

L. M. Lara, Trevor Fulton, Miriam Rengel, M. R. Kidger, G. A. Blake, R. Moreno, Emmanuel Jehin, E. Lellouch, Michael Küppers, David A. Naylor, C. Waelkens, D. C. Lis, T. de Graauw, E. A. Bergin, Jean Manfroid, M. I. Blecka, T. Encrenaz, M. de Val-Borro, L. Decin, J. Crovisier, Slawomira Szutowicz, Christopher Jarchow, Bart Vandenbussche, José Cernicharo, J. A. D. L. Blommaert, Damien Hutsemekers, N. Thomas, Paul Hartogh, Dominique Bockelée-Morvan, Alexander S. Medvedev, Sarah Leeks, Marek Banaszkiewicz, Rudolf Schieder, P. J. Encrenaz, F. Bensch, B. M. Swinyard, N. Biver, Martin Emprechtinger, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Rutherford Appleton Laboratory, Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Institut d'Astrophysique, Géophysique et Océanographie, Université de Liège, European Space Astronomy Centre (ESAC), Agence Spatiale Européenne = European Space Agency (ESA), Instituto de Astrofisica de Andalucia, CSIC (IAA), Space Research Centre, Polish Academy of Sciences (Wroclaw), Deutsches Zentrum für Luft- und Raumfahrt (DLR), Blue Sky Spectroscopy (BSS), Herschel Science Center, ESAC/ESA, Astronomy Department, University of Michigan, Centro de Astrobiología, Consejo Superior de Investigaciones Científicas (CSIC)/Instituto Nacional de Técnica Aeroespacial (INTA) (CAB), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Instrumentation et télédétection, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique et Atmosphères = Laboratory for Studies of Radiation and Matter in Astrophysics and Atmospheres (LERMA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Dynamique des milieux interstellaires et plasmas stellaires, SRON Netherlands Institute for Space Research, Department of Physics, University of Lethbridge, Lulea University of Technology (LTU), and University of Bern (UBERN)

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Physics, Range (particle radiation), Continuum (design consultancy), Comet, FOS: Physical sciences, Astronomy and Astrophysics, Coma (optics), Astrophysics, Spectral line, Radio telescope, Spire, Space and Planetary Science, Spectral energy distribution, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract

Comet C/2006 W3 (Christensen) was observed in November 2009 at 3.3 AU from the Sun with Herschel. The PACS instrument acquired images of the dust coma in 70- and 160-micrometers filters, and spectra covering several H2O rotational lines. Spectra in the range 450-1550 GHz were acquired with SPIRE. The comet emission continuum from 70 to 672 micrometers was measured, but no lines were detected. The spectral energy distribution indicates thermal emission from large particles and provides a measure of the size distribution index and dust production rate. The upper limit to the water production rate is compared to the production rates of other species (CO, CH3OH, HCN, H2S, OH) measured with the IRAM 30-m and Nancay telescopes. The coma is found to be strongly enriched in species more volatile than water, in comparison to comets observed closer to the Sun. The CO to H2O production rate ratio exceeds 220%. The dust to gas production rate ratio is on the order of 1., Accepted for publication in Astronomy & Astrophysics (special issue on Herschel first results)

Published
2010

26. The Herschel-Heterodyne Instrument for the Far-Infrared (HIFI)

Author

Brian Jackson, B. Kopf, R. Bieber, R. Güsten, A. M. di Giorgio, J. A. Stern, Holger S. P. Müller, B. J. van Leeuwen, G. S. Liu, R. Orfei, Neal R. Erickson, R. Lai, B. Delforges, Wolfgang Wild, Christian Leinz, O. Coeur-Joly, J. Desbat, David Teyssier, S. D. Lord, Karl Jacobs, Bruce Bumble, Lorene Samoska, M. Rataj, R. H. Lin, Dominicus Kester, M. Salez, X. Tielens, Alexandre Karpov, Paolo Saraceno, K. Edwards, R. Huisman, A. Megej, K. F. Schuster, Michel Fich, L. Dubbeldam, Serguei Cherednichenko, H. Golstein, Christian Monstein, J. A. Murphy, C. van Baaren, Victor Belitsky, P. Planesas, E. Natale, Michael Olberg, Lorenzo Piazzo, T. Peacock, Martin Eggens, Emmanuel Caux, W. A. Hatch, Neil Trappe, Hubregt J. Visser, Herbert Zirath, Jaap Evers, S. Phillip-May, Alain Maestrini, Hamid Javadi, Jacob Kooi, Th. de Graauw, F. Schmülling, E. C. Honingh, C. McCoey, J. C. Pearson, W. Luinge, I. Lopez-Fernandez, W. M. Laauwen, M. Michalska, Bengt Larsson, S. Wulff, John Gill, René Liseau, Volker Ossenkopf, Colin Borys, B. Kruizenga, Rafael Teipen, C. Kramer, A. Cros, H. Goulooze, P. Cais, W. Nowosielski, Goutam Chattopadhyay, M. Stokroos, Rafael Bachiller, F. Zwart, C. Gal, Piotr Orleanski, J. Kawamura, H. Smit, O. Siebertz, H. Aarts, Francesco Nuzzolo, L. Meinsma, Jonas Zmuidzinas, R. Assendorp, D. A. Beintema, H. van de Stadt, Jesús Martín-Pintado, G. de Lange, Ryszard Szczerba, Erich Schlecht, R. Higgins, Christophe Risacher, Patrick W. Morris, H. Jacobs, Christopher Jarchow, Willem Jellema, Pieter Dieleman, Todd Gaier, B. Franke, J. Stutzki, Imran Mehdi, Th. Klein, Harald Franz Arno Merkel, T. Finn, M. Justen, P.R. Wesselius, M. Ciechanowicz, T. M. Klapwijk, Hans-Joachim Wunsch, C. Comito, P. Zaal, Erik L. Kollberg, C. Diez-Gonzalez, T. den Boggende, John Ward, Jian-Rong Gao, Pasquale Cerulli-Irelli, C. Kasemann, T. Kuhn, Frank Helmich, K. Wildeman, Henry G. LeDuc, L. Ravera, Frank Maiwald, Y. Delorme, D. Moratschke, F. Schlöder, J. M. Krieg, M. Olbrich, A. Marston, Juan Daniel Gallego, P.-P. Kooiman, E. Steinmetz, T. Gunsing, A. Naber, M. Melchior, Geert Keizer, M. Schultz, I. Peron, S. Gauffre, C. K. Wafelbakker, N. Whyborn, M. Krause, T. Tils, Alexander Loose, A. de Jonge, Pieter R. Roelfsema, Rudolf Schieder, M. Caris, S. Glenz, A. Barcia, W. Baechtold, Paul Hartogh, R. Shipman, Adwin Boogert, Arnold O. Benz, Thomas G. Phillips, California Institute of Technology (CALTECH), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Sciences et Technologies - Bordeaux 1, Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Department of Microtechnology and Nanoscience (MC2), Chalmers University of Technology [Gothenburg, Sweden], Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Dept Pathol & Microbiol, Université de Montréal (UdeM)-Faculté de médecine vétérinaire, Leibniz Institute for Crystal Growth, Leibniz Institute, Technische Universität Darmstadt (TU Darmstadt), Instituto de RadioAstronomía Milimétrica (IRAM), Centre National de la Recherche Scientifique (CNRS), Institut für Festkörpertheorie, Westfälische Wilhelms-Universität Münster (WWU), Institute of Molecular Medicine and Cell Research (ZBMZ), University of Freiburg [Freiburg], Onsala Space Observatory, Chalmers University of Technology [Göteborg], ESO, European Southern Observatory (ESO), Istituto di Fisica dello Spazio Interplanetario (IFSI), Consiglio Nazionale delle Ricerche (CNR), Max Planck Institute for Meteorology (MPI-M), Institut für Chemie und Dynamik der Geosphäre - Troposphäre (ICG-2), Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association-Helmholtz-Gemeinschaft = Helmholtz Association, Herschel Science Center [Madrid], European Space Astronomy Centre (ESAC), European Space Agency (ESA)-European Space Agency (ESA), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), École normale supérieure - Paris (ENS-PSL), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Technische Universität Darmstadt - Technical University of Darmstadt (TU Darmstadt), Westfälische Wilhelms-Universität Münster = University of Münster (WWU), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Agence Spatiale Européenne = European Space Agency (ESA)-Agence Spatiale Européenne = European Space Agency (ESA), TNO Industrie en Techniek, and Astronomy

Subjects
Experimental Physics, Local oscillator, Observatories, Orbits, general [Submillimeter], 01 natural sciences, 7. Clean energy, spectroscopic [Techniques], law.invention, Far infrared, Spectrographs, law, spectrographs [Instrumentation], 010303 astronomy & astrophysics, instrumentation: spectrographs, Physics, Spectrometers, submillimeter: general, Bolometers, Correlators, methods: observational, infrared: general, Heterodyne, Frequency band, Submillimeter: generals, Instantaneous phase, Radio spectrum, Optics, Mixers (machinery), 0103 physical sciences, Frequency bands, observational [Methods], 010306 general physics, Remote sensing, techniques: spectroscopic, Spectrometer, business.industry, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Bolometer, generals [Submillimeter], Astronomy and Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Launching, general [Infrared], Space and Planetary Science, Heterodyning, Instruments, business
Abstract

International audience; Aims: This paper describes the Heterodyne Instrument for the Far-Infrared (HIFI) that was launched onboard ESA's Herschel Space Observatory in May 2009. Methods: The instrument is a set of 7 heterodyne receivers that are electronically tuneable, covering 480-1250 GHz with SIS mixers and the 1410-1910 GHz range with hot electron bolometer (HEB) mixers. The local oscillator (LO) subsystem comprises a Ka-band synthesizer followed by 14 chains of frequency multipliers and 2 chains for each frequency band. A pair of auto-correlators and a pair of acousto-optical spectrometers process the two IF signals from the dual-polarization, single-pixel front-ends to provide instantaneous frequency coverage of 2 × 4 GHz, with a set of resolutions (125 kHz to 1 MHz) that are better than 0.1 km s-1. Results: After a successful qualification and a pre-launch TB/TV test program, the flight instrument is now in-orbit and completed successfully the commissioning and performance verification phase. The in-orbit performance of the receivers matches the pre-launch sensitivities. We also report on the in-orbit performance of the receivers and some first results of HIFI's operations. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Published
2010

27. The Herschel-SPIRE submillimetre spectrum of Mars

Author

José Cernicharo, M. de Val-Borro, L. Decin, J. A. D. L. Blommaert, Ganna Portyankina, M. Renge, R. Moreno, Edwin A. Bergin, M. I. Blecka, Sarah Leeks, B. M. Swinyard, T. Encrenaz, Michael Kueppers, Geoffrey A. Blake, J. Crovisier, Emmanuel Jehin, N. Biver, Matthew Joseph Griffin, E. Lellouch, L. M. Lara, F. Bensch, Dariusz C. Lis, P. J. Encrenaz, G. S. Orton, G. Davis, Daphne Stam, C. Waelkens, Alexander S. Medvedev, Dominique Bockelée-Morvan, H. J. Walker, Christopher Jarchow, Régis Courtin, Bart Vandenbussche, Eva Verdugo, Paul Hartogh, Marek Banaszkiewicz, Rudolf Schieder, Hideo Sagawa, Nicolas Thomas, Thibault Cavalié, Slawomira Szutowicz, Trevor Fulton, M. R. Kidger, Sunil Sidher, T. de Graauw, David A. Naylor, F. Billebaud, Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Center for Mathematics and Physics, University of Aizu, Polska Akademia Nauk = Polish Academy of Sciences (PAN), Space Research Centre of Polish Academy of Sciences (CBK), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Laboratoire Optimisation de la Conception et Ingénierie de l'Environnement (LOCIE), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centro de Investigaciones Biológicas (CSIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Observatoire de Paris - Site de Paris (OP), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), Department of Ecology and Evolutionary Biology [Princeton], Princeton University, Instituut voor Sterrenkunde [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), SRON Netherlands Institute for Space Research (SRON), Centre Alexis Vautrin (CAV), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), and École normale supérieure - Paris (ENS-PSL)

Subjects
010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Fourier transform spectrometers, FOS: Physical sciences, Astrophysics, 01 natural sciences, Planet, 0103 physical sciences, Mixing ratio, Calibration, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, QB, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Atmospheric models, Detector, Astronomy and Astrophysics, Mars Exploration Program, Computational physics, 13. Climate action, Space and Planetary Science, Earth and Planetary Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics, Data reduction
Abstract

We have obtained the first continuous disk averaged spectrum of Mars from 450 to 1550 Ghz using the Herschel-SPIRE Fourier Transform Spectrometer. The spectrum was obtained at a constant resolution of 1.4 GHz across the whole band. The flux from the planet is such that the instrument was operated in "bright source" mode to prevent saturation of the detectors. This was the first successful use of this mode and in this work we describe the method used for observing Mars together with a detailed discussion of the data reduction techniques required to calibrate the spectrum. We discuss the calibration accuracy obtained and describe the first comparison with surface and atmospheric models. In addition to a direct photometric measurement of the planet the spectrum contains the characteristic transitions of 12CO from J 5-4 to J 13-12 as well as numerous H2O transitions. Together these allow the comparison to global atmospheric models allowing the mean mixing ratios of water and 12CO to be investigated. We find that it is possible to match the observed depth of the absorption features in the spectrum with a fixed water mixing ratio of 1 x 10-4 and a 12CO mixing ratio of 9 x 10-4, Accepted for publication in Astronomy&Astrophysics, Herschel First Results special issue

Published
2010

28. HIFI observations of warm gas in DR21: Shock versus radiative heating

Author

Markus Röllig, Rolf Güsten, M. Akyilmaz, Christopher Jarchow, S. D. Lord, Brian Jackson, T. Klein, Robert Simon, Andrew I. Harris, Carsten Kramer, Bhaswati Mookerjea, O. Coeur-Joly, F. F. S. van der Tak, D. Teyssier, Yoko Okada, Javier R. Goicoechea, C. Joblin, J. R. Rizzo, Asunción Fuente, Juergen Stutzki, Olivier Berné, Harold W. Yorke, Bruce Bumble, M. C. Diez-Gonzalez, David A. Neufeld, R. Higgins, Jesús Martín-Pintado, Arnold O. Benz, Thomas G. Phillips, F. Boulanger, D. A. Beintema, Maryvonne Gerin, C. Dedes, Peter G. Martin, Juan Daniel Gallego, Volker Ossenkopf, Nicola Schneider, Laboratoire Univers et Théories (LUTH (UMR_8102)), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), Physikalisches Institut [Köln], Universität zu Köln, Helmholtz zentrum für Schwerionenforschung GmbH (GSI), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), foreign laboratories (FL), CERN [Genève], Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Center for Astrophysics and Space Astronomy [Boulder] (CASA), University of Colorado [Boulder], Observatorio Astronómico Nacional (OAN), oan, Division for Submm Technologies, Max-Planck-Institut für Radioastronomie (MPIFR), CRUK Medical Oncology Unit, The Churchill Hospital, University of Michigan [Ann Arbor], University of Michigan System, Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Instituto de RadioAstronomía Milimétrica (IRAM), Centre National de la Recherche Scientifique (CNRS), CITA, University of Toronto, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), KOSMA, I. Physikalisches Institut, European Space Astronomy Centre (ESAC), European Space Agency (ESA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Universität zu Köln = University of Cologne, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Observatorio Astronomico Nacional, Madrid, Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Agence Spatiale Européenne = European Space Agency (ESA), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Astronomy

Subjects
HII regions, STAR-FORMING REGION, ISM: structure, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Spectral line, PHOTON-DOMINATED REGIONS, 0103 physical sciences, Cluster (physics), ABSORPTION, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, Line (formation), Physics, ISM: kinematics and dynamics, 010308 nuclear & particles physics, Star formation, DR-21, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, CLOUD, ISM: molecules, Shock (mechanics), Star cluster, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), submillimeter: ISM, Outflow, EMISSION, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Excitation
Abstract

The molecular gas in the DR21 massive star formation region is known to be affected by the strong UV field from the central star cluster and by a fast outflow creating a bright shock. The relative contribution of both heating mechanisms is the matter of a long debate. By better sampling the excitation ladder of various tracers we provide a quantitative distinction between the different heating mechanisms. HIFI observations of mid-J transitions of CO and HCO+ isotopes allow us to bridge the gap in excitation energies between observations from the ground, characterizing the cooler gas, and existing ISO LWS spectra, constraining the properties of the hot gas. Comparing the detailed line profiles allows to identify the physical structure of the different components. In spite of the known shock-excitation of H2 and the clearly visible strong outflow, we find that the emission of all lines up to > 2 THz can be explained by purely radiative heating of the material. However, the new Herschel/HIFI observations reveal two types of excitation conditions. We find hot and dense clumps close to the central cluster, probably dynamically affected by the outflow, and a more widespread distribution of cooler, but nevertheless dense, molecular clumps., Accepted for publication by A&A

Published
2010

29. Water and related chemistry in the solar system. A guaranteed time key programme for Herschel

Author

Slawomira Szutowicz, Michael Küppers, M. R. Kidger, N. Biver, David A. Naylor, Sunil Sidher, Emmanuel Jehin, M. I. Blecka, Dariusz C. Lis, Jean Manfroid, A. Gonzalez, Rudolf Schieder, Christopher Jarchow, Marek Banaszkiewicz, F. Billebaud, Régis Courtin, T. de Graauw, Ganna Portyankina, B. M. Swinyard, José Cernicharo, H. Walker, L. Decin, Bart Vandenbussche, F. Bensch, Gary R. Davis, P. J. Encrenaz, E. Verdugo, J. Crovisier, Thibault Cavalié, Paul Hartogh, A. de Lange, G. S. Orton, Hideo Sagawa, Nicolas Thomas, E. A. Bergin, R. Lorente, Alexander S. Medvedev, Dominique Bockelée-Morvan, G. D. Thornhill, Daphne Stam, Damien Hutsemekers, J. A. D. L. Blommaert, M. Sanchez-Portal, Geoffrey A. Blake, L. M. Lara, Emmanuel Lellouch, Thérèse Encrenaz, Miriam Rengel, R. Moreno, C. Waelkens, Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Space Research Centre of Polish Academy of Sciences (CBK), Polska Akademia Nauk = Polish Academy of Sciences (PAN), Harvard-Smithsonian Center for Astrophysics (CfA), Smithsonian Institution-Harvard University [Cambridge], Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Optimisation de la Conception et Ingénierie de l'Environnement (LOCIE), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centro de Investigaciones Biológicas (CSIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Observatoire de Paris - Site de Paris (OP), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), Department of Ecology and Evolutionary Biology [Princeton], Princeton University, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Departamento de Biologia Celular, Facultad de Biologia, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), European Southern Observatory (ESO), Laboratorio de Ecologia Isotopica, Centro de Energia Nuclear na Agricultura (CENA), California Institute of Technology (CALTECH), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Center for Mathematics and Physics, University of Aizu, SRON Netherlands Institute for Space Research (SRON), Centre Alexis Vautrin (CAV), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Harvard University-Smithsonian Institution, Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), and École normale supérieure - Paris (ENS-PSL)

Subjects
Herschel spaceobservatory Water Mars Giant planets Titan Comets, Solar System, Outer planets, 010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Comet, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], 01 natural sciences, Astrobiology, Interplanetary dust cloud, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Enceladus, 010303 astronomy & astrophysics, Physics::Atmospheric and Oceanic Physics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Physics, Chemistry, Astronomy, Astronomy and Astrophysics, Mars Exploration Program, Atmosphere of Mars, 13. Climate action, Space and Planetary Science, Physics::Space Physics, Astrophysics::Earth and Planetary Astrophysics
Abstract

International audience; "Water and related chemistry in the Solar System" is a Herschel Space Observatory Guaranteed-Time Key Programme. This project, approved by the European Space Agency, aims at determining the distribution, the evolution and the origin of water in Mars, the outer planets, Titan, Enceladus and the comets. It addresses the broad topic of water and its isotopologues in planetary and cometary atmospheres. The nature of cometary activity and the thermodynamics of cometary comae will be investigated by studying water excitation in a sample of comets. The D/H ratio, the key parameter for constraining the origin and evolution of Solar System species, will be measured for the first time in a Jupiter-family comet. A comparison with existing and new measurements of D/H in Oort-cloud comets will constrain the composition of pre-solar cometary grains and possibly the dynamics of the protosolar nebula. New measurements of D/H in giant planets, similarly constraining the composition of proto-planetary ices, will be obtained. The D/H and other isotopic ratios, diagnostic of Mars' atmosphere evolution, will be accurately measured in H2O and CO. The role of water vapor in Mars' atmospheric chemistry will be studied by monitoring vertical profiles of H2O and HDO and by searching for several other species (and CO and H2O isotopes). A detailed study of the source of water in the upper atmosphere of the Giant Planets and Titan will be performed. By monitoring the water abundance, vertical profile, and input fluxes in the various objects, and when possible with the help of mapping observations, we will discriminate between the possible sources of water in the outer planets (interplanetary dust particles, cometary impacts, and local sources). In addition to these inter-connected objectives, serendipitous searches will enhance our knowledge of the composition of planetary and cometary atmospheres.

Published
2009

31. Mesospheric vertical thermal structure and winds on Venus from HHSMT CO spectral-line observations

Author

Miriam Rengel, Christopher Jarchow, and Paul Hartogh

Subjects
Physics, biology, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Venus, biology.organism_classification, Atmospheric sciences, Astrophysics, Spectral line, Mesosphere, Atmosphere of Venus, Atmosphere, Warm front, Space and Planetary Science, Zonal flow, Radiative transfer
Abstract

We report vertical thermal structure and wind velocities in the Venusian mesosphere retrieved from carbon monoxide (12CO J=2-1 and 13CO J=2-1) spectral line observations obtained with the Heinrich Hertz Submillimeter Telescope (HHSMT). We observed the mesosphere of Venus from two days after the second Messenger flyby of Venus (on June 5 2007 at 23:10 UTC) during five days. Day-to-day and day-to-night temperature variations and short-term fluctuations of the mesospheric zonal flow were evident in our data. The extensive layer of warm air detected recently by SPICAV at 90 - to 100 km altitude is also detected in the temperature profiles reported here. These data were part of a coordinated ground-based Venus observational campaign in support of the ESA Venus Express mission. Furthermore, this study attempts to cross-calibrate space- and ground-based observations, to constrain radiative transfer and retrieval algorithms for planetary atmospheres, and to contribute to a more thorough understanding of the global patterns of circulation of the Venusian atmosphere., Comment: 35 pages, 18 figures. Shortcut URL to this page: http://www.sciencedirect.com/science/journal/00320633

Published
2008
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32. MIRO: Microwave Instrument for Rosetta Orbiter

Author

T. Koch, Margaret A. Frerking, Peter Schloerb, W-H. Ip, Christopher Jarchow, Paul Hartogh, E. Lellouch, Y. Salinas, Duane O. Muhleman, Dominique Bockelée-Morvan, Th. Encrenaz, R. Nowicki, N. Biver, E. Steinmetz, Mark Allen, A. Deschamps, Samuel Gulkis, P. J. Encrenaz, Didier Despois, Jacques Crovisier, J. M. Krieg, Heike Rauer, L. W. Kamp, Mark Hofstadter, M. A. Janssen, R. Irigoyen, Thomas R. Spilker, Ingrid Mann, Gerard Beaudin, P. C. Stek, M. Gheudin, C. Kahn, C. Backus, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), and Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010504 meteorology & atmospheric sciences, Comet, 01 natural sciences, law.invention, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Telescope, Orbiter, Optics, law, MIRO, 0103 physical sciences, Rosetta, comets, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Radiometer, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Spacecraft, Spectrometer, business.industry, Parabolic reflector, Astronomy and Astrophysics, submillimeter spectroscopy, Space and Planetary Science, Asteroid, business, spacecraft instruments
Abstract

The European Space Agency Rosetta Spacecraft, launched on March 2, 2004 toward Comet 67P/Churyumov-Gerasimenko, carries a relatively small and lightweight millimeter-submillimeter spectrometer instrument, the first of its kind launched into deep space. The instrument will be used to study the evolution of outgassing water and other molecules from the target comet as a function of heliocentric distance. During flybys of the asteroids (2867) Steins and (21) Lutetia in 2008 and 2010 respectively, the instrument will measure thermal emission and search for water vapor in the vicinity of these asteroids. The instrument, named MIRO (Microwave Instrument for the Rosetta Orbiter), consists of a 30-cm diameter, offset parabolic reflector telescope followed by two heterodyne receivers. Center-band operating frequencies of the receivers are near 190 GHz (1.6 mm) and 562 GHz (0.5 mm). Broadband continuum channels are implemented in both frequency bands for the measurement of near surface temperatures and temperature gradients in Comet 67P/Churyumov-Gerasimenko and the asteroids (2867) Steins and (21) Lutetia. A 4096 channel CTS (Chirp Transform Spectrometer) spectrometer having 180 MHz total bandwidth and 44 kHz resolution is, in addition to the continuum channel, connected to the submillimeter receiver. The submillimeter radiometer/spectrometer is fixed tuned to measure four volatile species – CO, CH3OH, NH3 and three, oxygen-related isotopologues of water, H2 16O, H2 17O and H2 18O. The basic quantities measured with the MIRO instrument are surface temperature, gas production rates and relative abundances, and velocity and excitation temperature of each species, along with their spatial and temporal variability. This paper provides a short discussion of the scientific objectives of the investigation, and a detailed discussion of the MIRO instrument system.

Published
2007

33. MIRO observations of subsurface temperatures of the nucleus of 67P/Churyumov-Gerasimenko

Author

Gerard Beaudin, Mathieu Choukroun, Christopher Jarchow, Nicolas Biver, Holger Sierks, Paul Hartogh, H. U. Keller, Mark Hofstadter, F. Peter Schloerb, Samuel Gulkis, Dominique Bockelée-Morvan, C. Leyrat, Stephen Keihm, Michael Janssen, Pierre Encrenaz, Jacques Crovisier, Robert Gaskell, Paul von Allmen, Wing-Huen Ip, Laurent Jorda, Emmanuel Lellouch, Ladislav Rezac, Seungwon Lee, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Institute of Astronomy [Taiwan] (IANCU), National Central University [Taiwan] (NCU), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut für Geophysik und Extraterrestrische Physik [Braunschweig] (IGEP), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], German Aerospace Center (DLR), École normale supérieure - Paris (ENS Paris), Max Planck Institute for Solar System Research (MPS), and Max-Planck-Institut für Sonnensystemforschung (MPS)

Subjects
Physics, Brightness, Astronomy and Astrophysics, Astrophysics, Latitude, law.invention, Orbiter, Wavelength, medicine.anatomical_structure, [SDU]Sciences of the Universe [physics], 13. Climate action, Space and Planetary Science, law, Brightness temperature, medicine, Sublimation (phase transition), Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Nucleus, Astrophysics::Galaxy Astrophysics, Microwave
Abstract

International audience; Observations of the nucleus of 67P/Churyumov-Gerasimenko in the millimeter-wave continuum have been obtained by the Microwave Instrument for the Rosetta Orbiter (MIRO). We present data obtained at wavelengths of 0.5 mm and 1.6 mm during September 2014 when the nucleus was at heliocentric distances between 3.45 and 3.27 AU. The data are fit to simple models of the nucleus thermal emission in order to characterize the observed behavior and make quantitative estimates of important physical parameters, including thermal inertia and absorption properties at the MIRO wavelengths. MIRO brightness temperatures on the irregular surface of 67P are strongly affected by the local solar illumination conditions, and there is a strong latitudinal dependence of the mean brightness temperature as a result of the seasonal orientation of the comet's rotation axis with respect to the Sun. The MIRO emission exhibits strong diurnal variations, which indicate that it arises from within the thermally varying layer in the upper centimeters of the surface. The data are quantitatively consistent with very low thermal inertia values, between 10-30 JK(-1) m(-2) s(-1/2), with the 0.5 mm emission arising from 1 cm beneath the surface and the 1.6 mm emission from a depth of 4 cm. Although the data are generally consistent with simple, homogeneous models, it is difficult to match all of its features, suggesting that there may be some vertical structure within the upper few centimeters of the surface. The MIRO brightness temperatures at high northern latitudes are consistent with sublimation of ice playing an important role in setting the temperatures of these regions where, based on observations of gas and dust production, ice is known to be sublimating.

Published
2015

34. Dark side of comet 67P/Churyumov-Gerasimenko in Aug.–Oct. 2014

Author

Wing-Huen Ip, Laurent Jorda, Christopher Jarchow, F. P. Schloerb, Holger Sierks, C. Leyrat, Pierre Encrenaz, Samuel Gulkis, Jacques Crovisier, M. A. Janssen, Mark Hofstadter, Emmanuel Lellouch, P. von Allmen, B. Gaskell, Sukhan Lee, Mathieu Choukroun, Paul Hartogh, Horst Uwe Keller, N. Biver, Dominique Bockelée-Morvan, Stephen Keihm, Ladislav Rezac, Gerard Beaudin, Laboratoire d'Astrophysique de Marseille (LAM), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Brightness, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Polar night, Astronomy, Astronomy and Astrophysics, Astrophysics, law.invention, Orbiter, 13. Climate action, Space and Planetary Science, law, Highly porous, Thermal, Radiative transfer, Polar, Millimeter
Abstract

International audience; The high obliquity (similar to 50 degrees) of comet 67P/Churyumov-Gerasimenko (67P) is responsible for a long-lasting winter polar night in the southern regions of the nucleus. We report observations made with the submillimeter and millimeter continuum channels of the Microwave Instrument onboard the Rosetta Orbiter (MIRO) of the thermal emission from these regions during the period August-October 2014. Before these observations, the southern polar regions had been in darkness for approximately five years. Subsurface temperatures in the range 25 50 K are measured. Thermal model calculations of the nucleus near-surface temperatures carried out over the orbit of 67P, coupled with radiative transfer calculations of the MIRO channels brightness temperatures, suggest that these regions have a thermal inertia within the range 10-60 Jm(-2) K-1 s(-0.5). Such low thermal inertia values are consistent with a highly porous, loose, regolith-like surface. These values are similar to those derived elsewhere on the nucleus. A large difference in the brightness temperatures measured by the two MIRO continuum channels is tentatively attributed to dielectric properties that differ significantly from the sunlit side, within the first few tens of centimeters. This is suggestive of the presence of ice(s) within the MIRO depths of investigation in the southern polar regions. These regions started to receive sunlight in May of 2015, and refinements of the shape model in these regions, as well as continuing MIRO observations of 67P, will allow refining these results and reveal the thermal properties and potential ice content of the southern regions in more detail.

Published
2015

35. First detection of the 63μm atomic oxygen line in the thermosphere of Mars with GREAT/SOFIA

Author

Heiko Richter, Ladislav Rezac, Paul Hartogh, Heinz-Wilhelm Hübers, Christopher Jarchow, Rolf Güsten, N. Honingh, Helmut Wiesemeyer, and Bernd Klein

Subjects
Martian, Physics, Stratospheric Observatory for Infrared Astronomy, Airglow, Mars, Astronomy and Astrophysics, Mars Exploration Program, Atmosphere of Mars, Astrophysics, terahertz, Atmosphere, Space and Planetary Science, Radiative transfer, GREAT, Astrophysics::Earth and Planetary Astrophysics, Thermosphere, SOFIA, oxygen
Abstract

Context. The Stratospheric Observatory for Infrared Astronomy (SOFIA) with its 2.5 m telescope provides new science opportunities for spectroscopic observations of planetary atmospheres in the far-infrared wavelength range.Aims. This paper presents first results from the 14 May, 2014 observing campaign of the Martian atmosphere at 4.7 THz using the German REceiver for Astronomy at Terahertz frequencies (GREAT) instrument.Methods. The atomic oxygen 63 μ m transition, OI, was detected in absorption against the Mars continuum, with a high signal-to-noise ratio (~35). A beam-averaged atomic oxygen from a global circulation model was used as input to the radiative transfer simulations of the observed line area and to obtain a new estimate on the column density using a grid-search method.Results. Minimizing differences between the calculated and observed line intensities in the least-square sense yields an atomic oxygen column density of (1.1 ± 0.2) × 1017 cm-2 . This value is about twice as low as predicted by a modern photochemical model of Mars. The radiative transfer simulations indicate that the line forms in the upper atmospheric region over a rather extended altitude region of 70–120 km.Conclusions. For the first time, a far-infrared transition of the atomic oxygen line was detected in the atmosphere of Mars. The absorption depth provides an estimate on the column density, and this measurement provides additional means to constrain the photochemical models in global circulation models and airglow studies. The lack of other means for monitoring the atomic oxygen in the Martian upper atmosphere makes future observations with the SOFIA observatory highly desirable.

Published
2015

36. On the spatiotemporal behavior of ozone within the upper mesosphere/mesopause region under nearly polar night conditions

Author

Mykhaylo Grygalashvyly, Christopher Jarchow, G. R. Sonnemann, and Paul Hartogh

Subjects
Atmospheric Science, Daytime, Ozone, Ecology, Polar night, Advection, Paleontology, Soil Science, Forestry, Aquatic Science, Oceanography, Atmospheric sciences, Latitude, chemistry.chemical_compound, Geophysics, chemistry, Space and Planetary Science, Geochemistry and Petrology, Middle latitudes, Mesopause, Earth and Planetary Sciences (miscellaneous), Mixing ratio, Earth-Surface Processes, Water Science and Technology
Abstract

[1] The spatiotemporal behavior of the ozone mixing ratio in the upper mesosphere/mesopause region under nearly polar night conditions is one of the phenomena not completely understood and reproduced by models thus far. We examine this issue using an advanced three-dimensional model of the dynamics and chemistry of the middle atmosphere (0–150 km) particularly designed to investigate the spatiotemporal structure of this phenomenon in the extended mesopause region. The most marked features of the modeling results are a pronounced ozone maximum around 72 km occurring close to the polar night terminator and a strong drop of the mixing ratio above ∼80 km. These features were also found by means of ground-based microwave measurements in high latitude at the Arctic Lidar Observatory for Middle Atmosphere Research (ALOMAR, 69.29°N, 16.03°E) and even at the moderate latitude of Lindau (51.66°N, 10.13°E) during the night in the winter season but less marked there. They were absent at both stations during the daytime hours. The calculations suggest that the stronger enhanced ozone values occur in a latitudinal band of approximately 15° in the vicinity of the polar night terminator. During nighttime, enhanced values reach into midlatitudes. The effect is confined both to a height interval approximately between 66 and 76 km and to a certain latitudinal range which alters with season according to the change of the polar night terminator. We discuss the model results in terms of chemistry for nearly grazing incidence conditions of the solar insolation and in context with advective transport.

Published
2004

38. Analysis of forward models using the singular value decomposition algorithm

Author

Paul Hartogh and Christopher Jarchow

Subjects
Atmospheric composition, Nonlinear system, Singular value decomposition, Microwave remote sensing, Inversion (meteorology), Parameter space, Inverse problem, Algorithm, Mathematics
Abstract

For microwave remote sensing of atmospheric composition or temperature an inversion of the measured primary data is in general necessary to obtain the desired profiles. In addition to the atmospheric quantities some unknown instrumental parameters might also need to be estimated from the data. Especially when designing a new instrument the question arises, whether the suggested data set contains enough information to retrieve the profiles and parameters with the desired accuracy. The singular value decomposition algorithm is shown to be a universal and powerful tool to analyze any linear or moderately nonlinear forward model and quantify the amount of retrievable parameters. In addition the method can be used as a simple and robust inversion technique, thus giving in one step not only an analysis of the relationship between measurement and parameter space, but also a solution of the inverse problem. The application of this method is illustrated using data obtained by ground-based measurements of ozone at 142 GHz.

Published
1997

39. Ground-based microwave detection of middle atmospheric ozone

Author

Christopher Jarchow and Paul Hartogh

Subjects
Heterodyne, Data processing, Meteorology, Spectrometer, business.industry, Optical engineering, Environmental science, business, Automation, Atmospheric ozone, Microwave, Remote sensing, Microwave detection
Abstract

A groundbased microwave heterodyne spectrometer for the monitoring of the vertical distribution of middle atmospheric ozone has been developed at our institute. It has supplied data since the end of 1992. Because standalone operation has been planned, one important design goal of the instrument was to achieve a high degree of automation. In this paper an overview of the instrument is given and some of the long term data are presented.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Published
1995

40. Ground-based detection of middle atmospheric water vapor

Author

Paul Hartogh and Christopher Jarchow

Subjects
Heterodyne, Spectrometer, law, Chemistry, Optical engineering, Superheterodyne receiver, Chirp, Spectroscopy, Microwave, Water vapor, Remote sensing, law.invention
Abstract

Groundbased microwave measurements are well suited for the intercomparison and validation of satellite data. A microwave heterodyne spectrometer, which can be used for this purpose has been developed at our institute. It measures the 22.235 GHz water vapor spectral emission and supplies water vapor profiles in the altitude range from 35 to 85 km with a time resolution of one day. The instrument, consisting of a cooled heterodyne receiver frontend and a chirp transform spectrometer (CTS) backend is described and water vapor profiles are presented.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Published
1995

41. Retrieval of data from ground-based microwave sensing of the middle atmosphere: comparison of two inversion techniques

Author

Christopher Jarchow and Paul Hartogh

Subjects
Troposphere, Geography, Optimal estimation, Data quality, A priori and a posteriori, Inversion (meteorology), Atmospheric model, Microwave, Remote sensing, Trace gas
Abstract

In microwave remote sensing of atmospheric trace gases a retrieval technique described by C. D. Rodgers as optimal estimation has widely been adopted during recent years. We found out some difficulties in applying this method to the analysis of long term groundbased observations due to the large variability of the tropospheric transmission. The corresponding changes of the data quality and the weight of the a priori profile in the inversion algorithm can lead to an artificial correlation between the retrieved profiles and the transmission. In addition an assessment of the inversion only from the error bars of the profile is impossible since they don't respond linearly to the errors of the spectra. It is shown, that an inversion algorithm according to Backus-Gilbert's philosophy will avoid these difficulties.

Published
1995

42. Herschelmeasurements of the D/H and16O/18O ratios in water in the Oort-cloud comet C/2009 P1 (Garradd)

Author

Miriam Rengel, G. A. Blake, R. Moreno, E. Lellouch, N. Biver, Dominique Bockelée-Morvan, Sunil Sidher, Christopher Jarchow, J. Crovisier, B. M. Swinyard, Michael Küppers, Paul Hartogh, Gary R. Davis, Martin Emprechtinger, David A. Naylor, H. J. Walker, D. C. Lis, Régis Courtin, Trevor Fulton, M. R. Kidger, Slawomira Szutowicz, M. de Val-Borro, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Cahill Center for Astronomy and Astrophysics, California Institute of Technology (CALTECH), Instituto de Astrofisica de Canarias (IAC), European Space Astronomy Centre (ESAC), Agence Spatiale Européenne = European Space Agency (ESA), University of Lethbridge, Space Science and Technology Department [Didcot] (RAL Space), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), Max-Planck-Institut für Sonnensystemforschung (MPS), and European Space Agency (ESA)

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), [PHYS]Physics [physics], Physics, education.field_of_study, Planetesimal, 010504 meteorology & atmospheric sciences, Population, Comet, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Space observatory, 13. Climate action, Space and Planetary Science, 0103 physical sciences, Water excitation, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], education, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Astrophysics - Earth and Planetary Astrophysics, 0105 earth and related environmental sciences
Abstract

The D/H ratio in cometary water is believed to be an important indicator of the conditions under which icy planetesimals formed and can provide clues to the contribution of comets to the delivery of water and other volatiles to Earth. Available measurements suggest that there is isotopic diversity in the comet population. The Herschel Space Observatory revealed an ocean-like ratio in the Jupiter-family comet 103P/Hartley 2, whereas most values measured in Oort-cloud comets are twice as high as the ocean D/H ratio. We present here a new measurement of the D/H ratio in the water of an Oort-cloud comet. HDO, H_2O, and H_2^18O lines were observed with high signal-to-noise ratio in comet C/2009 P1 (Garradd) using the Herschel HIFI instrument. Spectral maps of two water lines were obtained to constrain the water excitation. The D/H ratio derived from the measured H_2^16O and HDO production rates is 2.06+/-0.22 X 10**-4. This result shows that the D/H in the water of Oort-cloud comets is not as high as previously thought, at least for a fraction of the population, hence the paradigm of a single, archetypal D/H ratio for all Oort-cloud comets is no longer tenable. Nevertheless, the value measured in C/2009 P1 (Garradd) is significantly higher than the Earth's ocean value of 1.558 X 10**-4. The measured H_2^16O/H_2^18O ratio of 523+/-32 is, however, consistent with the terrestrial value., Comment: 6 pages with 4 figures and 1 table. Accepted for publication as a Letter in Astronomy & Astrophysics

Published
2012

43. HIFI observations of water in the atmosphere of comet C/2008 Q3 (Garradd)

Author

L. M. Lara, Miriam Rengel, T. Klein, Nicolas Biver, M. R. Kidger, R. Moreno, Emmanuel Jehin, E. Lellouch, Michael Küppers, C. Kasemann, David A. Naylor, C. Waelkens, Pieter Dieleman, T. de Graauw, Dominique Bockelée-Morvan, Michael Olberg, E. A. Bergin, Pieter R. Roelfsema, M. Caris, Jean Manfroid, M. I. Blecka, T. Encrenaz, M. de Val-Borro, L. Decin, J. Crovisier, Slawomira Szutowicz, Christopher Jarchow, Bart Vandenbussche, José Cernicharo, J. A. D. L. Blommaert, Damien Hutsemekers, N. Thomas, Geoffrey A. Blake, Rolf Guesten, Paul Hartogh, Alexander S. Medvedev, Marek Banaszkiewicz, Arnold O. Benz, Rudolf Schieder, P. J. Encrenaz, F. Bensch, B. M. Swinyard, Dariusz C. Lis, Thibault Cavalié, Martin Emprechtinger, Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), California Institute of Technology (CALTECH), Space Research Centre of Polish Academy of Sciences (CBK), Polska Akademia Nauk = Polish Academy of Sciences (PAN), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), European Southern Observatory (ESO), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Laboratoire Optimisation de la Conception et Ingénierie de l'Environnement (LOCIE), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centro de Investigaciones Biológicas (CSIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Instituut voor Sterrenkunde [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Centre Alexis Vautrin (CAV), Max-Planck-Institut für Radioastronomie (MPIFR), Onsala Space Observatory, Chalmers University of Technology [Göteborg], Astronomy, Max Planck Institute for Solar System Research (MPS), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1, Smithsonian Institution-Harvard University [Cambridge], and École normale supérieure - Paris (ENS Paris)

Subjects
ROTATIONAL-EXCITATION, Electron density, 010504 meteorology & atmospheric sciences, Mean kinetic temperature, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Infrared, Comet, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Astrophysics, 01 natural sciences, RADIATIVE-TRANSFER, 0103 physical sciences, Radiation trapping, Spectroscopy, 010303 astronomy & astrophysics, SATELLITE, 0105 earth and related environmental sciences, Line (formation), Earth and Planetary Astrophysics (astro-ph.EP), Physics, LEE, submillimeter: general, Astronomy and Astrophysics, MODEL, 13. Climate action, Space and Planetary Science, comets: individual: C/2008 Q3, ODIN, VAPOR, radio lines: general, techniques: spectroscopic, Excitation, Astrophysics - Earth and Planetary Astrophysics
Abstract

High-resolution far-infrared and sub-millimetre spectroscopy of water lines is an important tool to understand the physical and chemical properties of cometary atmospheres. We present observations of several rotational ortho- and para-water transitions in comet C/2008 Q3 (Garradd) performed with HIFI on Herschel. These observations have provided the first detection of the 2_{12}-1_{01} (1669 GHz) ortho and 1_{11}-0_{00} (1113 GHz) para transitions of water in a cometary spectrum. In addition, the ground-state transition 1_{10}-1_{01} at 557 GHz is detected and mapped. By detecting several water lines quasi-simultaneously and mapping their emission we can constrain the excitation parameters in the coma. Synthetic line profiles are computed using excitation models which include excitation by collisions, solar infrared radiation, and radiation trapping. We obtain the gas kinetic temperature, constrain the electron density profile, and estimate the coma expansion velocity by analyzing the map and line shapes. We derive water production rates of 1.7-2.8 x 10^{28} s^{-1} over the range r_h = 1.83-1.85 AU., Comment: 7 figures, v2: minor changes, updated version of arXiv:1005.2969v1. Accepted for publication in Astronomy and Astrophysics, Herschel special issue on Herschel First Science Results

Published
2010

44. The HCN molecule as a tracer of the nucleus rotation of comet 73P-C/Schwassmann-Wachmann 3

Author

Michael Küppers, Geronimo Villanueva, Christopher Jarchow, Lucas Paganini, Paul Hartogh, and Michal Drahus

Subjects
Rotation period, Physics, Comet, Astronomy, Astronomy and Astrophysics, Context (language use), Coma (optics), Astrophysics, Rotation, Light curve, medicine.anatomical_structure, Space and Planetary Science, medicine, Nucleus, Line (formation)
Abstract

Context. The causes of cometary break-ups are still uncertain. One suggested mechanism is splitting due to fast rotation of the nucleus. This can be tested by measuring rotation periods of cometary fragments.Aims. The exceptionally close approach of the split comet 73P/Schwassmann-Wachmann 3 to the Earth in May 2006 made it an ideal target to investigate the rotation of its fragments. We used the HCN light curve for this purpose, because it is particularly sensitive to the rotation of the nucleus and at the same time it allows us to study the physics of cometary activity.Methods. Comet 73P/Schwassmann-Wachmann 3 was observed between May 1 and 22, 2006, with the Submillimeter Telescope on Mt. Graham, Arizona, USA. Emission from HCN and CS were clearly detected. In this work we focus exclusively on the observations of the HCN molecule in fragment C, obtained during five nights between May 10 and 22, 2006, which provide the best S/N and the best temporal coverage.Results. The light curve of comet 73P-C/Schwassmann-Wachmann 3 in HCN shows strong non-random variations, most probably stimulated by the nucleus rotation. The variability has an amplitude of about a factor of 2 on a time scale of hours. Among several plausible solutions for periodicity, we found strong indications for a rotation period of between 3.0 and 3.4 h, consistent with the determination from the Hubble Space Telescope. At 1 AU from the Sun the mean-diurnal HCN production rate was 2.7 1025 molec s-1 (with an uncertainty of about 20%) and the coma was expanding with a velocity of 0.8 ± 0.1 km s-1 . The line position was evolving with a phase angle that is visible in the night-averaged spectra.Conclusions. Evolution of the line position is consistent with the solar-stimulated activity. The mean-diurnal HCN production rate should be considered as very high, and it requires an unusually large fraction of the nucleus area to be active, whereas the coma expansion velocity was typical. The proposed rotation period, being the shortest ever determined for a cometary nucleus, cautiously suggests the disruption of the parent body due to a large centrifugal force, though it cannot be considered as a proof of this scenario. On the other hand, the observed stability of 73P-C against the rotational disruption suggests a bulk tensile strength of at least 14–45 Pa. The rotation period was surprisingly stable, indicating that no more than about 0.2% of the total outgassing was effectively accelerating or decelerating the nucleus spin. This is consistent with the large active fraction of the nucleus.

Published
2010

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