Search

Your search keyword '"Barnes, J.W."' showing total 223 results
Start Over Author "Barnes, J.W."
223 results on '"Barnes, J.W."'

1. Novel Proteins Implicated in Extracellular Matrix Remodeling and Angiogenesis Are Upregulated in Pulmonary Arterial Hypertension

Author

Jones, L.I., primary, Sridhar, M., additional, Howze, P.H., additional, Vang, S., additional, Easter, M., additional, Matthews, E.L., additional, Hirsch, M.J., additional, Burpee, B., additional, Harris, E., additional, Lora Gonzalez, M., additional, Kyle, J., additional, Clair, G.C.D., additional, Krick, S., additional, and Barnes, J.W., additional

Published
2024
Full Text
View/download PDF

19. Observations of a stationary mid-latitude cloud system on Titan

Author

Adamkovics, M., Barnes, J.W., Hartung, M., and De Pater, I.

Subjects
Astronomy, Clouds, Astronomy, Earth sciences
Abstract

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2010.03.006 Byline: M. Adamkovics (a), J.W. Barnes (b), M. Hartung (c), I. de Pater (a) Keywords: Infrared observations; Meteorology; Radiative transfer Abstract: We report the observation of a cloud system on Titan that remained localized near 40[degrees]S latitude and 60[degrees]W longitude for at least 34h. Ground-based observations obtained with the SINFONI imaging spectrograph at the Very Large Telescope over four consecutive nights recorded the lifetime and altitude of the unresolved cloud system. Concomitant measurements made by Cassini/VIMS over 3h resolved changes in the altitude and opacity of individual regions within the system during this time. Clouds are measured from 13 to 37km altitude with optical depths per pixel ranging from I=0.13 to 7. Short timescale rise times are consistent with previous measurements of the evolution of mid-latitude clouds; however the long timescale localization of the cloud structure is unexplained. We speculate about the role of mesoscale circulation in relation to cloud formation. Author Affiliation: (a) Astronomy Department, University of California, 601 Campbell Hall, Berkeley, CA 94720-3411, USA (b) Department of Physics, University of Idaho, Moscow, ID 83844-0903, USA (c) Gemini Observatory, Southern Operations Center, Casilla 603, La Serena, Chile Article History: Received 10 December 2009; Revised 3 March 2010; Accepted 4 March 2010

Published
2010

20. The identification of liquid ethane in Titan's Ontario Lacus

Author

Brown, R.H., Soderblom, L.A., Soderblom, J.M., Clark, R.N., Jaumann, R., Barnes, J.W., Sotin, C., Buratti, B., and Baines, K.H. & Nicholson, P.D.

Subjects
Titan (Satellite) -- Chemical properties, Titan (Satellite) -- Discovery and exploration, Ethanes -- Discovery and exploration, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Titan was once thought to have global oceans of light hydrocarbons on its surface (1-5), but after 40 close flybys of Titan by the Cassini spacecraft, it has become clear [...]

Published
2008

21. Using group theory and transition matrices to study a class of metaheuristic neighborhoods

Author

Barnes, J.W., Colletti, Bruce W., and Neuway, David L.

Subjects
Search theory, Heuristic -- Research, Business, Business, general, Business, international
Abstract

A class of metaheuristic neighborhoods are studied, using group theory and transition matrices. A transition matrix represents a one-step conjugative rearrangement neighborhood of the possible incumbent tours in an n-city single-agent Traveling Salesperson Problem.

Published
2002

36. Novel Anti-Aging Strategies to Inhibit the Effect of Bronchial Cell Senescence on Mucociliary Dysfunction

Author

Krick, S., primary, Garth, J., additional, Adewale, A.T., additional, Shei, R.-J., additional, Tang, L.P., additional, Helton, E.S., additional, Denson, R., additional, Zaharias, R., additional, King, G., additional, Sailland, J., additional, Kunzi, L., additional, Baumlin, N., additional, Salathe, M.A., additional, Rowe, S.M., additional, and Barnes, J.W., additional

Published
2019
Full Text
View/download PDF

39. The Cassini VIMS archive of Titan: From browse products to global infrared color maps

Author

Le Mouélic, S., primary, Cornet, T., additional, Rodriguez, S., additional, Sotin, C., additional, Seignovert, B., additional, Barnes, J.W., additional, Brown, R.H., additional, Baines, K.H., additional, Buratti, B.J., additional, Clark, R.N., additional, Nicholson, P.D., additional, Lasue, J., additional, Pasek, V., additional, and Soderblom, J.M., additional

Published
2019
Full Text
View/download PDF

42. Titan's Magic Island: Transient Features in a Titan Sea

Author

Hofgartner, J. D., Hayes, Alexander G., Lunine, Jonathan I., Zebker, H., Stiles, B. W., Sotin, C., Barnes, J.W., Turtle, E. P., Baines, K. H., Brown, B. H., Buratti, B. J., Clark, R. N., Encrenaz, P., Kirk, R. D., Le Gall, Alice, Lopes, Rosaly M., Lorenz, Ralph D., Malaska, Michael, Mitchell, Karl L., Nicholson, Philip, Paillou, Philippe, Radebaugh, Jani, Wall, S.D., Wood, Charles, Department of Astronomy [Ithaca], Cornell University [New York], Department of Electrical Engineering [Stanford], Stanford University, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), University of Idaho [Moscow, USA], Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), University of Arizona, US Geological Survey [Denver], United States Geological Survey [Reston] (USGS), 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), Astrogeology Science Center [Flagstaff], PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), ASP 2015, 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), Department of Geological Sciences [BYU], Brigham Young University (BYU), Planetary Science Institute [Tucson] (PSI), École normale supérieure - Paris (ENS-PSL), 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 Pomies, Marie-Paule

Subjects
[SDU.ASTR.EP]Sciences of the Universe [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]
Abstract

International audience; Titan's Magic Island/Waves, solids, or bubbles/Which can it be?/Come to this talk and see!

Published
2015

43. The Case of Titan's Mysterious New Island: Analysis of Anomalously Bright Features Observed in the Cassini T92 SAR Pass Over Titan's Ligeia Mare

Author

Hofgartner, J. D., Hayes, A. G., Lunine, J.I., Zebker, H., Stiles, B., Sotin, C., Barnes, J.W., Brown, B. H., Encrenaz, P., Kirk, R. D., Le Gall, Alice, Lopes, R. M., Lorenz, R. D., Malaska, M., Mitchell, K. L., Paillou, Philippe, Radebaugh, J., Turtle, E., Wall, S., Wood, C., Pomies, Marie-Paule, Department of Astronomy [Ithaca], Cornell University [New York], Department of Electrical Engineering [Stanford], Stanford University, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Department of Physics [Moscow,USA], University of Idaho [Moscow, USA], University of Arizona, 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), Astrogeology Science Center [Flagstaff], United States Geological Survey [Reston] (USGS), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), 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), Department of Geological Sciences [BYU], Brigham Young University (BYU), Planetary Science Institute [Tucson] (PSI), Cassini Radar, École normale supérieure - Paris (ENS-PSL), 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), and 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)

Subjects
[PHYS.ASTR.EP] Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [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], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience; Anomalous features were detected in Ligeia Mare that were not in any preceding nor subsequent observations. They are unique on Titan or transient in nature.

Published
2014

44. Global characterization of Titan's dune fields by RADAR and VIMS observations

Author

Garcia, A., Rodriguez, S., Lucas, A., Appéré, T., Le Gall, Alice, Reffet, E., Le Corre, L., Le Mouélic, S., Cornet, T., Courrech Du Pont, S., Narteau, C., Bourgeois, O., Radebaugh, J., Arnold, K., Barnes, J.W., Sotin, C., Brown, R. H., Lorenz, R. D., Turtle, E. P., Astrophysique Interprétation Modélisation (AIM (UMR7158 / 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), Centre d'Etude de Saclay, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Planetary Science Institute [Tucson] (PSI), 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), Matière et Systèmes Complexes (MSC), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Department of Geological Sciences [BYU], Brigham Young University (BYU), Department of Physics [Moscow,USA], University of Idaho [Moscow, USA], Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Lunar and Planetary Laboratory [Tucson] (LPL), University of Arizona, Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), 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), IMPEC - LATMOS, Laboratoire de Planétologie et Géodynamique UMR6112 (LPG), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Université d'Angers (UA), Matière et Systèmes Complexes (MSC (UMR_7057)), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), California Institute of Technology (CALTECH)-NASA, and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)

Subjects
[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]
Abstract

International audience; Cassini/RADAR high-resolution images of Titan's surface revealed linear features, geomorphologically similar to longitudinal dunes. Those dunes cover a large portion of the whole surface of Titan, i.e 7.8%, and 13.4% are present on the 58.4% of the surface imaged by the RADAR/SAR from July 2004 to July 2013 (fig.1). 99.6% of the dunes are confined at the equatorial regions (30°N-30°S). Formed and sculpted by the wind, those features represent clues for the understanding of the climatic history on the satellite. By using the joint analysis between RADAR/SAR observations and the infrared VIMS mosaic corrected for atmospheric contributions acquired through July 2013 and June 2010 respectively, we found a very high degree of correlation at global scale (more than 70%) between the RADAR dunes and a specific infrared VIMS spectral unit, the "dark brown unit". Some RADAR dunes, less than 2%, also belong in a commonly referenced unit, the "dark blue unit". These two units have been delimited by defining for each a specific set of spectral criteria. We have shown that those two units present a spectral behavior different, especially at short wavelengths (below 2 µm) allowing to say that the "dark brown unit" is dominated by organic sediment, similar to atmospheric aerosols, namely tholins, and the "dark blue" is most likely enriched in water ice compared to the rest of Titan's surface. Given the strong correlation between RADAR dunes and the infrared "dark brown unit" we are now able to extrapolate the total surface area of the dunes material to the total surface area of the "dark brown unit" which correspond to 17% of the Titan's surface. This permits to estimate the volume of sediment of 360,000 km3 (total mass ≈ 290,000 GT). Thus, these estimates based on the RADAR dunes/VIMS units correlation make the dune fields the largest organic reservoir on Titan's surface and characterize more precisely the composition of the dune material over the total extend of the dune regions.

Published
2013

46. Cryovolcanic Features on Titan

Author

Lopes, Rosaly M.C., Stofan, E.R., Kirk, R.L, Mitchell, K.L., Le Gall, Alice, Barnes, J.W., Hayes, A., Kargel, J., Radebaugh, J., Janssen, M.A., Neish, C.D., Wood, C., Wall, S.D., Lunine, J., Malaska, M.J., Cardon, Catherine, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Proxemy Research Inc, Astrogeology Science Center [Flagstaff], United States Geological Survey [Reston] (USGS), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Physics [Moscow,USA], University of Idaho [Moscow, USA], Department of Astronomy [Ithaca], Cornell University [New York], Department of Hydrology and Water Resources, University of Arizona, Department of Geological Sciences [BYU], Brigham Young University (BYU), NASA Goddard Space Flight Center (GSFC), and Department of Hydrology and Atmospheric Sciences [University of Arizona]

Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [PHYS.ASTR.EP] Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [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], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [PHYS.PHYS.PHYS-AO-PH] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]
Abstract

International audience; We present evidence to support the cryovolcanic origin of some features, which includes the deepest pit known on Titan (Sotra Patera) and some of the highest mountains (Doom and Erebor Montes). We interpret this region to be a cryovolcanic complex of multiple cones, craters, and flows. Elsewhere, a circular feature, approximately 100 km across, is morphologically similar to a laccolith, showing a cross pattern interpreted to be extensional fractures. However, we find that some other previously supposed cryovolcanic features were likely formed by other processes. We discuss implications for eruption style and composition of cryovolcanism on Titan. Our analysis shows the great value of combining data sets when interpreting Titan's geology and in particular stresses the value of topographic data

Published
2013

48. Equinoctial Activity Over Titan Dune Fields Revealed by Cassini/vims

Author

Rodriguez, S., Le Mouélic, S., Barnes, J.W., Hirtzig, M., Rannou, Pascal, Sotin, C., Brown, R. H., Bow, J., Vixie, G., Cornet, T., Bourgeois, Olivier, Narteau, C., Courrech Du Pont, S., Le Gall, Alice, Reffet, E., Griffith, C. A., Jaumann, R., Stephan, K., Buratti, B. J., Clarke, R. N., Baines, Kevin H., Nicholson, P. D., Coustenis, A., Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), 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), 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), University of Idaho [Moscow, USA], 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), Groupe de spectrométrie moléculaire et atmosphérique (GSMA), Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), California Institute of Technology (CALTECH)-NASA, Department of Planetary Sciences [Tucson], University of Arizona, Institut de Physique du Globe de Paris, Matière et Systèmes Complexes (MSC (UMR_7057)), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), DLR Institute of Planetary Research, German Aerospace Center (DLR), United States Geological Survey [Reston] (USGS), Space Science and Engineering Center [Madison] (SSEC), University of Wisconsin-Madison, Department of Astronomy [Ithaca], Cornell University [New York], Cardon, Catherine, Laboratoire de Planétologie et Géodynamique UMR6112 (LPG), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Université d'Angers (UA), 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 Pierre et Marie Curie - Paris 6 (UPMC), NASA-California Institute of Technology (CALTECH), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), IMPEC - LATMOS, Cornell University, Astrophysique Interprétation Modélisation (AIM (UMR7158 / 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), Institut de Physique du Globe de Paris (IPG Paris), and Matière et Systèmes Complexes (MSC)

Subjects
[SDU.ASTR.EP]Sciences of the Universe [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]
Abstract

International audience; Titan, the largest satellite of Saturn, is the only satellite in the solar system with a dense atmosphere. The close and continuous observations of Titan by the Cassini spacecraft, in orbit around Saturn since July 2004, bring us evidences that Titan troposphere and low stratosphere experience an exotic, but complete meteorological cycle similar to the Earth hydrological cycle, with hydrocarbons evaporation, condensation in clouds, and rainfall. Cassini monitoring campaigns also demonstrate that Titan's cloud coverage and climate vary with latitude. Titan's tropics, with globally weak meteorological activity and widespread dune fields, seem to be slightly more arid than the poles, where extensive and numerous liquid reservoirs and sustained cloud activity have been discovered. Only a few tropo-spheric clouds have been observed at Titan's tropics during the southern summer. As equinox was approaching (in August 2009), they occurred more frequently and appeared to grow in strength and size. We present here the observation of intense brightening at Titan's tropics, very close to the equinox. These detections were conducted with the Visual and Infrared Mapping Spectrometer (VIMS) onboard Cassini. We will discuss the VIMS images of the three individual events detected so far, observed during the Titan's flybys T56 (22 May 2009), T65 (13 January 2010) and T70 (21 June 2010). T56, T65 and T70 observations show an intense and transient brighten-ing of large regions very close to the equator, right over the extensive dune fields of Senkyo, Belet and Shangri-La. They all appear spectrally and morphologically different from all transient surface features or atmospheric phenomena previously reported. Indeed, these events share in particular a strong brightening at wavelengths greater than 2 μm (especially at 5 μm), making them spectrally distinct from the small tropical clouds observed before the equinox and the large storms observed near the equator in September and October 2010. In this paper, we will discuss the possibility that these singular events may have occurred very close to the surface, having a strong link with the underlying dune fields. Radiative transfer calculations indeed show that these singular brightenings are due to the transient appearance of an additional atmospheric layer, confined at very low altitudes and loaded with few but large particles. Gathering all the observational and modeling constraints, we conclude that the most probable explanation for these events is the local and transient occurrence of huge sand storms, directly originating from the underlying dune fields. We will also discuss the possible implications of the equinoctial occurrence of such events for Titan's tropical wind regimes and for the present-day activity of equatorial dunes.

Published
2012

49. Equinoctial atmospheric activity over Titan dune fiels revealed by Cassini/VIMS

Author

Rodriguez, S., Le Mouélic, S., Barnes, J.W., Hirtzig, M., Rannou, Pascal, Sotin, C., Brown, R. H., Bow, J., Vixie, G., Cornet, T., Bourgeois, O., Narteau, C., Courrech Du Pont, S., Le Gall, Alice, Reffet, E., Griffith, C. A., Jaumann, R., Stephan, K., Buratti, B. J., Clark, R. N., Baines, K. H., Nicholson, P. D., Coustenis, Athéna, Astrophysique Interprétation Modélisation (AIM (UMR7158 / 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), 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), University of Idaho [Moscow, USA], 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), Groupe de spectrométrie moléculaire et atmosphérique (GSMA), Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Department of Planetary Sciences [Tucson], University of Arizona, Institut de Physique du Globe de Paris (IPG Paris), Matière et Systèmes Complexes (MSC), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), DLR Institute of Planetary Research, German Aerospace Center (DLR), United States Geological Survey [Reston] (USGS), Space Science and Engineering Center [Madison] (SSEC), University of Wisconsin-Madison, Department of Astronomy [Ithaca], Cornell University [New York], Lunar and Planetary Institute, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), 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), California Institute of Technology (CALTECH)-NASA, Institut de Physique du Globe de Paris, Matière et Systèmes Complexes (MSC (UMR_7057)), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Cardon, Catherine, Laboratoire de Planétologie et Géodynamique UMR6112 (LPG), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Université d'Angers (UA), 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 Pierre et Marie Curie - Paris 6 (UPMC), IMPEC - LATMOS, Space Science Center, Science and Engineering Research Center, and Cornell University

Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [PHYS.PHYS.PHYS-AO-PH] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]
Abstract

International audience; Introduction: Titan, the largest satellite of Saturn, is the only satellite in the solar system with a dense atmosphere. The close and continuous observations of Titan by the Cassini spacecraft, in orbit around Saturn since July 2004, bring us evidences that Titan tropo-sphere and low stratosphere experience an exotic, but complete meteorological cycle similar to the Earth hy-drological cycle, with hydrocarbons evaporation, con-densation in clouds, and rainfall. Cassini monitoring campaigns also demonstrate that Titan's cloud cover-age and climate vary with latitude. Titan's tropics, with globally weak meteorological activity and widespread dune fields, seem to be slightly more arid than the poles, where extensive and numerous liquid reservoirs and sustained cloud activity were discovered. Only a few tropospheric clouds have been observed at Titan's tropics during the southern summer [1-4]. As equinox was approaching (in August 2009), they oc-curred more frequently and appeared to grow in strength and size [5-7]. VIMS observations: We present here the observa-tion of intense brightening at Titan's tropics, very close to the equinox. These detections were conducted with the Visual and Infrared Mapping Spectrometer [8] (VIMS) onboard Cassini. Figure 1 presents the VIMS color composite images of the three individual events detected so far, observed during the Titan's flybys T56 (22 May 2009), T65 (13 January 2010) and T70 (21 June 2010). T56, T65 and T70 observations show an intense and transient brightening of large regions very close to the equator, right over the extensive dune fields of Senkyo, Belet and Sangria-La. They all appear spectrally and morphologically different from all tran-sient surface features or atmospheric phenomena pre-viously reported. Indeed, these events share in particu-lar a strong brightening at wavelengths greater than 2 µm (especially at 5 µm), making them spectrally dis-tinct from the small tropical clouds observed before the equinox [1,3,7] and the large storms observed near the equator in September and October 2010 [6]. Discussion: In this paper, we will discuss the pos-sibility that these singular events may have occurred very close to the surface, having a strong link with the underlying dune fields. Radiative transfer calculations indeed show that these singular brightenings are due to the transient appearance of an additional atmospheric layer, confined at very low altitudes and loaded with few but large particles. Gathering all the observational and modeling constraints, we conclude that the most probable explanation for these events is the local and transient occurrence of huge dust storms, directly orig-inating from the underlying dune fields. We will also discuss the possible implications of the equinoctial occurrence of such events for Titan's tropical wind regimes and for the present-day activity of equatorial dunes.

Published
2012

50. Cassini/VIMS Spectra and Time-Evolution of Precipitation-Associated Surface Brightenings on Titan

Author

Barnes, J.W., Buratti, B.J., Turtle, E.P., Bow, J., Dalba, P.A., Perry, J., Rodriguez, S., Lé Mouélic, S., Baines, K.H., Sotin, C., Lorenz, R.D., Malaska, M.J., McCord, T.B., Brown, R.H., Clark, R.N., Jaumann, R., Hayne, P., Nicholson, P.D., Soderblom, J.M., and Soderblom, L.A.

Subjects
Planetengeologie, surface, Cassini, Titan
Abstract

Large areas of Titan’s surface brightened at all wavelengths as seen from Cassini/VIMS for several months. The brightenings occurred after a large storm and rainfall event, and may relate to volatile refreezing due to evaporative cooling.

Published
2012

Catalog

Books, media, physical & digital resources
See catalog results