240 results on '"Jones, Geraint H."'
Search Results
2. Imaging Polarimetry of Comet 67P/Churyumov-Gerasimenko: Homogeneous Distribution of Polarisation and its Implications
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Gray, Zuri, Bagnulo, Stefano, Boehnhardt, Hermann, Borisov, Galin, Jones, Geraint H., Kolokolova, Ludmilla, Kwon, Yuna G., Moreno, Fernando, Muñoz, Olga, Nežič, Rok, and Snodgrass, Colin
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Astrophysics - Earth and Planetary Astrophysics - Abstract
Comet 67P/Churyumov-Gerasimenko (67P) become observable for the first time in 2021 since the Rosetta rendezvous in 2014--16. Here, we present pre-perihelion polarimetric measurements of 67P from 2021 performed with the Very Large Telescope (VLT), as well as post-perihelion polarimetric measurements from 2015--16 obtained with the VLT and the William Herschel Telescope (WHT). This new data covers a phase angle range of ~4-50{\deg} and presents polarimetric measurements of unprecedentedly high S/N ratio. Complementing previous measurements, the polarimetric phase curve of 67P resembles that of other Jupiter family comets and high-polarisation, dusty comets. Comparing pre- and post-perihelion data sets, we find only a marginal difference between the polarimetric phase curves. In our imaging maps, we detect various linear structures produced by the dust in the inner coma of the comet. Despite this, we find a homogeneous spread of polarisation around the photocentre throughout the coma and tail, in contrast to previous studies. Finally, we explore the consequences of image misalignments on both polarimetric maps and aperture polarimetric measurements., Comment: 15 pages, 10 figures, 2 tables. Accepted for publication in MNRAS, May 13th 2024
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- 2024
3. Polarimetry of Didymos-Dimorphos: Unexpected Long-Term Effects of the DART Impact
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Gray, Zuri, Bagnulo, Stefano, Granvik, Mikael, Cellino, Alberto, Jones, Geraint H., Kolokolova, Ludmilla, Moreno, Fernando, Muinonen, Karri, Muñoz, Olga, Opitom, Cyrielle, Penttilä, Antti, and Snodgrass, Colin
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Astrophysics - Earth and Planetary Astrophysics - Abstract
We have monitored the Didymos-Dimorphos binary system in imaging polarimetric mode before and after the impact from the Double Asteroid Redirection Test (DART) mission. A previous spectropolarimetric study showed that the impact caused a dramatic drop in polarisation. Our longer-term monitoring shows that the polarisation of the post-impact system remains lower than the pre-impact system even months after the impact, suggesting that some fresh ejecta material remains in the system at the time of our observations, either in orbit or settled on the surface. The slope of the post-impact polarimetric curve is shallower than that of the pre-impact system, implying an increase in albedo of the system. This suggests that the ejected material is composed of smaller and possibly brighter particles than those present on the pre-impact surface of the asteroid. Our polarimetric maps show that the dust cloud ejected immediately after the impact polarises light in a spatially uniform manner (and at a lower level than pre-impact). Later maps exhibit a gradient in polarisation between the photocentre (which probes the asteroid surface) and the surrounding cloud and tail. The polarisation occasionally shows some small-scale variations, the source of which is not yet clear. The polarimetric phase curve of Didymos-Dimorphos resembles that of the S-type asteroid class., Comment: Accepted for publication in PSJ. 22 pages, 10 figures, 2 tables
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- 2023
4. Determining the dust environment of an unknown comet for a spacecraft fly-by: The case of ESA's Comet Interceptor mission
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Marschall, Raphael, Zakharov, Vladimir, Tubiana, Cecilia, Kelley, Michael S. P., van Damme, Carlos Corral, Snodgrass, Colin, Jones, Geraint H., Ivanovski, Stavro L., Postberg, Frank, Della Corte, Vincenzo, Vincent, Jean-Baptiste, Muñoz, Olga, La Forgia, Fiorangela, Levasseur-Regourd, Anny-Chantal, and Team, the Comet Interceptor
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
We present a statistical approach to assess the dust environment for a yet unknown comet (or when its parameters are known only with large uncertainty). This is of particular importance for missions such as ESA's Comet Interceptor mission to a dynamically new comet. We find that the lack of knowledge of any particular comet results in very large uncertainties (~3 orders of magnitude) for the dust densities within the coma. The most sensitive parameters affecting the dust densities are the dust size distribution, the dust production rate and coma brightness, often quantified by Af$\rho$. Further, the conversion of a coma's brightness (Af$\rho$) to a dust production rate is poorly constrained. The dust production rate can only be estimated down to an uncertainty of ~0.5 orders of magnitude if the dust size distribution is known in addition to the Af$\rho$. To accurately predict the dust environment of a poorly known comet, a statistical approach as we propose here needs to be taken to properly reflect the uncertainties. This can be done by calculating an ensemble of comae covering all possible combinations within parameter space as shown in this work., Comment: 27 pages, 15 figures, data available under https://www.doi.org/10.5281/zenodo.6906815
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- 2022
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5. The Comet Interceptor Mission
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Jones, Geraint H., Snodgrass, Colin, Tubiana, Cecilia, Küppers, Michael, Kawakita, Hideyo, Lara, Luisa M., Agarwal, Jessica, André, Nicolas, Attree, Nicholas, Auster, Uli, Bagnulo, Stefano, Bannister, Michele, Beth, Arnaud, Bowles, Neil, Coates, Andrew, Colangeli, Luigi, Corral van Damme, Carlos, Da Deppo, Vania, De Keyser, Johan, Della Corte, Vincenzo, Edberg, Niklas, El-Maarry, Mohamed Ramy, Faggi, Sara, Fulle, Marco, Funase, Ryu, Galand, Marina, Goetz, Charlotte, Groussin, Olivier, Guilbert-Lepoutre, Aurélie, Henri, Pierre, Kasahara, Satoshi, Kereszturi, Akos, Kidger, Mark, Knight, Matthew, Kokotanekova, Rosita, Kolmasova, Ivana, Kossacki, Konrad, Kührt, Ekkehard, Kwon, Yuna, La Forgia, Fiorangela, Levasseur-Regourd, Anny-Chantal, Lippi, Manuela, Longobardo, Andrea, Marschall, Raphael, Morawski, Marek, Muñoz, Olga, Näsilä, Antti, Nilsson, Hans, Opitom, Cyrielle, Pajusalu, Mihkel, Pommerol, Antoine, Prech, Lubomir, Rando, Nicola, Ratti, Francesco, Rothkaehl, Hanna, Rotundi, Alessandra, Rubin, Martin, Sakatani, Naoya, Sánchez, Joan Pau, Simon Wedlund, Cyril, Stankov, Anamarija, Thomas, Nicolas, Toth, Imre, Villanueva, Geronimo, Vincent, Jean-Baptiste, Volwerk, Martin, Wurz, Peter, Wielders, Arno, Yoshioka, Kazuo, Aleksiejuk, Konrad, Alvarez, Fernando, Amoros, Carine, Aslam, Shahid, Atamaniuk, Barbara, Baran, Jędrzej, Barciński, Tomasz, Beck, Thomas, Behnke, Thomas, Berglund, Martin, Bertini, Ivano, Bieda, Marcin, Binczyk, Piotr, Busch, Martin-Diego, Cacovean, Andrei, Capria, Maria Teresa, Carr, Chris, Castro Marín, José María, Ceriotti, Matteo, Chioetto, Paolo, Chuchra-Konrad, Agata, Cocola, Lorenzo, Colin, Fabrice, Crews, Chiaki, Cripps, Victoria, Cupido, Emanuele, Dassatti, Alberto, Davidsson, Björn J. R., De Roche, Thierry, Deca, Jan, Del Togno, Simone, Dhooghe, Frederik, Donaldson Hanna, Kerri, Eriksson, Anders, Fedorov, Andrey, Fernández-Valenzuela, Estela, Ferretti, Stefano, Floriot, Johan, Frassetto, Fabio, Fredriksson, Jesper, Garnier, Philippe, Gaweł, Dorota, Génot, Vincent, Gerber, Thomas, Glassmeier, Karl-Heinz, Granvik, Mikael, Grison, Benjamin, Gunell, Herbert, Hachemi, Tedjani, Hagen, Christian, Hajra, Rajkumar, Harada, Yuki, Hasiba, Johann, Haslebacher, Nico, Herranz De La Revilla, Miguel Luis, Hestroffer, Daniel, Hewagama, Tilak, Holt, Carrie, Hviid, Stubbe, Iakubivskyi, Iaroslav, Inno, Laura, Irwin, Patrick, Ivanovski, Stavro, Jansky, Jiri, Jernej, Irmgard, Jeszenszky, Harald, Jimenéz, Jaime, Jorda, Laurent, Kama, Mihkel, Kameda, Shingo, Kelley, Michael S. P., Klepacki, Kamil, Kohout, Tomáš, Kojima, Hirotsugu, Kowalski, Tomasz, Kuwabara, Masaki, Ladno, Michal, Laky, Gunter, Lammer, Helmut, Lan, Radek, Lavraud, Benoit, Lazzarin, Monica, Le Duff, Olivier, Lee, Qiu-Mei, Lesniak, Cezary, Lewis, Zoe, Lin, Zhong-Yi, Lister, Tim, Lowry, Stephen, Magnes, Werner, Markkanen, Johannes, Martinez Navajas, Ignacio, Martins, Zita, Matsuoka, Ayako, Matyjasiak, Barbara, Mazelle, Christian, Mazzotta Epifani, Elena, Meier, Mirko, Michaelis, Harald, Micheli, Marco, Migliorini, Alessandra, Millet, Aude-Lyse, Moreno, Fernando, Mottola, Stefano, Moutounaick, Bruno, Muinonen, Karri, Müller, Daniel R., Murakami, Go, Murata, Naofumi, Myszka, Kamil, Nakajima, Shintaro, Nemeth, Zoltan, Nikolajev, Artiom, Nordera, Simone, Ohlsson, Dan, Olesk, Aire, Ottacher, Harald, Ozaki, Naoya, Oziol, Christophe, Patel, Manish, Savio Paul, Aditya, Penttilä, Antti, Pernechele, Claudio, Peterson, Joakim, Petraglio, Enrico, Piccirillo, Alice Maria, Plaschke, Ferdinand, Polak, Szymon, Postberg, Frank, Proosa, Herman, Protopapa, Silvia, Puccio, Walter, Ranvier, Sylvain, Raymond, Sean, Richter, Ingo, Rieder, Martin, Rigamonti, Roberto, Ruiz Rodriguez, Irene, Santolik, Ondrej, Sasaki, Takahiro, Schrödter, Rolf, Shirley, Katherine, Slavinskis, Andris, Sodor, Balint, Soucek, Jan, Stephenson, Peter, Stöckli, Linus, Szewczyk, Paweł, Troznai, Gabor, Uhlir, Ludek, Usami, Naoto, Valavanoglou, Aris, Vaverka, Jakub, Wang, Wei, Wang, Xiao-Dong, Wattieaux, Gaëtan, Wieser, Martin, Wolf, Sebastian, Yano, Hajime, Yoshikawa, Ichiro, Zakharov, Vladimir, Zawistowski, Tomasz, Zuppella, Paola, Rinaldi, Giovanna, and Ji, Hantao
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- 2024
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6. Polarimetric analysis of STEREO observations of sungrazing Kreutz comet C/2010 E6 (STEREO)
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Nežič, Rok, Bagnulo, Stefano, Jones, Geraint H., Knight, Matthew M., and Borisov, Galin
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Astrophysics - Earth and Planetary Astrophysics - Abstract
Twin STEREO spacecraft pre-perihelion photometric and polarimetric observations of the sungrazing Kreutz comet C/2010 E6 (STEREO) in March 2010 at heliocentric distances $3-28~R_{\odot}$ were investigated using a newly-created set of analysis routines. The comet fully disintegrated during its perihelion passage. Prior to that, a broadening and an increase of the intensity peak with decreasing heliocentric distance was accompanied by a drop to zero polarisation at high phase angles (~105-135{\deg}, STEREO-B) and the emergence of negative polarisation at low phase angles (~25-35{\deg}, STEREO-A). Outside the near-comet region, the tail exhibited a steep slope of increasing polarisation with increasing cometocentric distance, with the slope becoming less prominent as the comet approached the Sun. The steep slope may be attributed to sublimation of refractory organic matrix and the processing of dust grains, or to presence of amorphous carbon. The change in slope with proximity to the Sun is likely caused by the gradual sublimation of all refractory material. The polarisation signatures observed at both sets of phase angles closer to the comet photocentre as the comet approached the Sun are best explained by fragmentation of the nucleus, exposing fresh Mg-rich silicate particles, followed by their gradual sublimation. The need for further studies of such comets, both observational and theoretical, is highlighted, as well as the benefit of the analysis routines created for this work., Comment: 13 pages, 9 figures, 1 table. Published by MNRAS in April 2022
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- 2020
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7. Heavy Positive Ion Groups in Titan's Ionosphere from Cassini Plasma Spectrometer IBS Observations
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Haythornthwaite, Richard P., Coates, Andrew J., Jones, Geraint H., Wellbrock, Anne, Waite, J. Hunter, Vuitton, Veronique, and Lavvas, Panayotis
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Astrophysics - Earth and Planetary Astrophysics ,Physics - Space Physics - Abstract
Titan's ionosphere contains a plethora of hydrocarbons and nitrile cations and anions as measured by the Ion Neutral Mass Spectrometer and Cassini Plasma Spectrometer (CAPS) onboard the Cassini spacecraft. Data from the CAPS Ion Beam Spectrometer (IBS) sensor have been examined for five close encounters of Titan during 2009. The high relative velocity of Cassini with respect to the cold ions in Titan's ionosphere allows CAPS IBS to function as a mass spectrometer. Positive ion masses between 170 and 310 u/q are examined with ion mass groups identified between 170 and 275 u/q containing between 14 and 21 heavy (carbon/nitrogen/oxygen) atoms. These groups are the heaviest positive ion groups reported so far from the available in situ ion data at Titan. The ion group peaks are found to be consistent with masses associated with Polycyclic Aromatic Compounds (PAC), including Polycyclic Aromatic Hydrocarbon (PAH) and nitrogen-bearing polycyclic aromatic molecular ions. The ion group peak identifications are compared with previously proposed neutral PAHs and are found to be at similar masses, supporting a PAH interpretation. The spacing between the ion group peaks is also investigated, finding a spacing of 12 or 13 u/q indicating the addition of C or CH. Lastly, the occurrence of several ion groups is seen to vary across the five flybys studied, possibly relating to the varying solar radiation conditions observed across the flybys. These findings further the understanding between the low mass ions and the high mass negative ions, as well as with aerosol formation in Titan's atmosphere.
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- 2020
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8. Exocomets from a Solar System Perspective
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Strøm, Paul A., Bodewits, Dennis, Knight, Matthew M., Kiefer, Flavien, Jones, Geraint H., Kral, Quentin, Matrà, Luca, Bodman, Eva, Capria, Maria Teresa, Cleeves, Ilsedore, Fitzsimmons, Alan, Haghighipour, Nader, Harrison, John H. D., Iglesias, Daniela, Kama, Mihkel, Linnartz, Harold, Majumdar, Liton, de Mooij, Ernst J. W., Milam, Stefanie N., Opitom, Cyrielle, Rebollido, Isabel, Rogers, Laura K., Snodgrass, Colin, Sousa-Silva, Clara, Xu, Siyi, Lin, Zhong-Yi, and Zieba, Sebastian
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Solar and Stellar Astrophysics - Abstract
Exocomets are small bodies releasing gas and dust which orbit stars other than the Sun. Their existence was first inferred from the detection of variable absorption features in stellar spectra in the late 1980s using spectroscopy. More recently, they have been detected through photometric transits from space, and through far-IR/mm gas emission within debris disks. As (exo)comets are considered to contain the most pristine material accessible in stellar systems, they hold the potential to give us information about early stage formation and evolution conditions of extra Solar Systems. In the Solar System, comets carry the physical and chemical memory of the protoplanetary disk environment where they formed, providing relevant information on processes in the primordial solar nebula. The aim of this paper is to compare essential compositional properties between Solar System comets and exocomets. The paper aims to highlight commonalities and to discuss differences which may aid the communication between the involved research communities and perhaps also avoid misconceptions. Exocomets likely vary in their composition depending on their formation environment like Solar System comets do, and since exocomets are not resolved spatially, they pose a challenge when comparing them to high fidelity observations of Solar System comets. Observations of gas around main sequence stars, spectroscopic observations of "polluted" white dwarf atmospheres and spectroscopic observations of transiting exocomets suggest that exocomets may show compositional similarities with Solar System comets. The recent interstellar visitor 2I/Borisov showed gas, dust and nuclear properties similar to that of Solar System comets. This raises the tantalising prospect that observations of interstellar comets may help bridge the fields of exocomet and Solar System comets., Comment: 25 pages, 3 figures. To be published in PASP. This paper is the product of a workshop at the Lorentz Centre in Leiden, the Netherlands
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- 2020
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9. Cometary ions detected by the Cassini spacecraft 6.5 au downstream of Comet 153P/Ikeya-Zhang
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Jones, Geraint H., Elliott, Heather A., McComas, David J., Hill, Matthew E., Vandegriff, Jon, Smith, Edward J., Crary, Frank J., and Waite, J. Hunter
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Astrophysics - Earth and Planetary Astrophysics ,Physics - Space Physics - Abstract
During March-April 2002, while between the orbits of Jupiter and Saturn, the Cassini spacecraft detected a significant enhancement in pickup proton flux. The most likely explanation for this enhancement was the addition of protons to the solar wind by the ionization of neutral hydrogen in the corona of comet 153P/Ikeya-Zhang. This comet passed relatively close to the Sun-Cassini line during that period, allowing pickup ions to be carried to Cassini by the solar wind. This pickup proton flux could have been further modulated by the passage of the interplanetary counterparts of coronal mass ejections past the comet and spacecraft. The radial distance of 6.5 Astronomical Units (au) traveled by the pickup protons, and the implied total tail length of >7.5 au make this cometary ion tail the longest yet measured., Comment: Submitted to Icarus
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- 2020
10. Prospects for the In Situ detection of Comet C/2019 Y4 ATLAS by Solar Orbiter
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Jones, Geraint H., Afghan, Qasim, and Price, Oliver
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Solar and Stellar Astrophysics - Abstract
The European Space Agency's Solar Orbiter spacecraft will pass approximately downstream of the position of comet C/2019 Y4 (ATLAS) in late May and early June 2020. We predict that the spacecraft may encounter the comet's ion tail around 2020 May 31-June 1, and that the comet's dust tail may be crossed on 2020 June 6. We outline the solar wind features and dust grain collisions that the spacecraft's instruments may detect when crossing the comet's two tails. Solar Orbiter will also pass close to the orbital path of C/2020 F8 (SWAN) on 2020 May 22, but we believe that it is unlikely to detect any material associated with that comet., Comment: 3 pages, 1 figure
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- 2020
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11. Potential Backup Targets for Comet Interceptor
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Schwamb, Megan E., Knight, Matthew M., Jones, Geraint H., Snodgrass, Colin, Bucci, Lorenzo, Perez, José Manuel Sánchez, and Skuppin, Nikolai
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Astrophysics - Earth and Planetary Astrophysics - Abstract
Comet Interceptor is an ESA F-class mission expected to launch in 2028 on the same launcher as ESA's ARIEL mission. Comet Interceptor's science payload consists of three spacecraft, a primary spacecraft that will carry two smaller probes to be released at the target. The three spacecraft will fly-by the target along different chords, providing multiple simultaneous perspectives of the comet nucleus and its environment. Each of the spacecraft will be equipped with different but complementary instrument suites designed to study the far and near coma environment and surface of a comet or interstellar object (ISO). The primary spacecraft will perform a fly-by at ~1000 km from the target. The two smaller probes will travel deeper into the coma, closer to the nucleus. The mission is being designed and launched without a specific comet designated as its main target. Comet Interceptor will travel to the Sun-Earth L2 Lagrangian point with ARIEL and wait in hibernation until a suitable long-period comet (LPC) is found that will come close enough to the Sun for the spacecraft to maneuver to an encounter trajectory. To prepare for all eventualities, the science team has assembled a preliminary set of backup targets from the known Jupiter family comets, where a suitable fly-by trajectory can be achieved during the nominal mission timeline (including the possibility of some launch delay). To better prioritize this list, we are releasing our potential backup targets in order to solicit the planetary community's help with observations of these objects over future apparitions and to encourage publication of archival data on these objects., Comment: Accepted to RNAAS
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- 2020
12. GAUSS - genesis of asteroids and evolution of the solar system: A sample return mission to Ceres
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Shi, Xian, Castillo-Rogez, Julie, Hsieh, Henry, Hui, Hejiu, Ip, Wing-Huen, Lei, Hanlun, Li, Jian-Yang, Tosi, Federico, Zhou, Liyong, Agarwal, Jessica, Barucci, Antonella, Beck, Pierre, Bagatin, Adriano Campo, Capaccioni, Fabrizio, Coates, Andrew J., Cremonese, Gabriele, Duffard, Rene, Grande, Manuel, Jaumann, Ralf, Jones, Geraint H., Kallio, Esa, Lin, Yangting, Mousis, Olivier, Nathues, Andreas, Oberst, Jürgen, Sierks, Holger, Ulamec, Stephan, and Wang, Mingyuan
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- 2022
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13. The in-situ exploration of Jupiter’s radiation belts
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Roussos, Elias, Allanson, Oliver, André, Nicolas, Bertucci, Bruna, Branduardi-Raymont, Graziella, Clark, George, Dialynas, Konstantinos, Dandouras, Iannis, Desai, Ravindra T., Futaana, Yoshifumi, Gkioulidou, Matina, Jones, Geraint H., Kollmann, Peter, Kotova, Anna, Kronberg, Elena A., Krupp, Norbert, Murakami, Go, Nénon, Quentin, Nordheim, Tom, Palmaerts, Benjamin, Plainaki, Christina, Rae, Jonathan, Santos-Costa, Daniel, Sarris, Theodore, Shprits, Yuri, Sulaiman, Ali, Woodfield, Emma, Wu, Xin, and Yao, Zonghua
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- 2022
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14. Comet Interceptor Mission
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Jones, Geraint H., primary, Snodgrass, Colin, additional, Tubiana, Cecilia, additional, and Küppers, Michael, additional
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- 2023
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15. Fine-scale structure in cometary dust tails II: Further evidence for a solar wind influence on cometary dust dynamics from the analysis of striae in comet C/2011 L4 Pan-STARRS
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Price, Oliver, Jones, Geraint H., Battams, Karl, and Owens, Mathew
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- 2023
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16. Effects of the 2007 Martian Global Dust Storm on Boundary Positions in the Induced Magnetosphere
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Regan, Catherine E., primary, Coates, Andrew J., additional, Lester, Mark, additional, Wellbrock, Anne, additional, Jones, Geraint H., additional, Sánchez-Cano, Beatriz, additional, Garnier, Philippe, additional, Haythornthwaite, Richard P., additional, Meggi, Dikshita, additional, Frahm, Rudy A., additional, and Holmström, Mats, additional
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- 2024
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17. The Plasma Environment of Comet 67P/Churyumov-Gerasimenko
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Goetz, Charlotte, Behar, Etienne, Beth, Arnaud, Bodewits, Dennis, Bromley, Steve, Burch, Jim, Deca, Jan, Divin, Andrey, Eriksson, Anders I., Feldman, Paul D., Galand, Marina, Gunell, Herbert, Henri, Pierre, Heritier, Kevin, Jones, Geraint H., Mandt, Kathleen E., Nilsson, Hans, Noonan, John W., Odelstad, Elias, Parker, Joel W., Rubin, Martin, Simon Wedlund, Cyril, Stephenson, Peter, Taylor, Matthew G. G. T., Vigren, Erik, Vines, Sarah K., and Volwerk, Martin
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- 2022
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18. Imaging Polarimetry of Comet 67 P/Churyumov–Gerasimenko: Homogeneous Distribution of Polarisation and its Implications
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Gray, Zuri, primary, Bagnulo, Stefano, additional, Boehnhardt, Hermann, additional, Borisov, Galin, additional, Jones, Geraint H, additional, Kolokolova, Ludmilla, additional, Kwon, Yuna G, additional, Moreno, Fernando, additional, Muñoz, Olga, additional, Nežič, Rok, additional, and Snodgrass, Colin, additional
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- 2024
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19. The perihelion activity of comet 67P/Churyumov-Gerasimenko as seen by robotic telescopes
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Snodgrass, Colin, Opitom, Cyrielle, de Val-Borro, Miguel, Jehin, Emmanuel, Manfroid, Jean, Lister, Tim, Marchant, Jon, Jones, Geraint H., Fitzsimmons, Alan, Steele, Iain A., Smith, Robert J., Jermak, Helen, Granzer, Thomas, Meech, Karen J., Rousselot, Philippe, and Levasseur-Regourd, Anny-Chantal
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Astrophysics - Earth and Planetary Astrophysics - Abstract
Around the time of its perihelion passage the observability of 67P/Churyumov-Gerasimenko from Earth was limited to very short windows each morning from any given site, due to the low solar elongation of the comet. The peak in the comet's activity was therefore difficult to observe with conventionally scheduled telescopes, but was possible where service/queue scheduled mode was possible, and with robotic telescopes. We describe the robotic observations that allowed us to measure the total activity of the comet around perihelion, via photometry (dust) and spectroscopy (gas), and compare these results with the measurements at this time by Rosetta's instruments. The peak of activity occurred approximately two weeks after perihelion. The total brightness (dust) largely followed the predictions from Snodgrass et al. 2013, with no significant change in total activity levels from previous apparitions. The CN gas production rate matched previous orbits near perihelion, but appeared to be relatively low later in the year., Comment: To appear in special issue of MNRAS "The ESLAB 50 Symposium - spacecraft at comets from 1P/Halley to 67P/Churyumov-Gerasimenko"
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- 2016
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20. Polarimetry of Didymos–Dimorphos: Unexpected Long-term Effects of the DART Impact
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Gray, Zuri, Bagnulo, Stefano, Granvik, Mikael, Cellino, Alberto, Jones, Geraint H., Kolokolova, Ludmilla, Moreno, Fernando, Muinonen, Karri, Muñoz, Olga, Opitom, Cyrielle, Penttilä, Antti, Snodgrass, Colin, Gray, Zuri, Bagnulo, Stefano, Granvik, Mikael, Cellino, Alberto, Jones, Geraint H., Kolokolova, Ludmilla, Moreno, Fernando, Muinonen, Karri, Muñoz, Olga, Opitom, Cyrielle, Penttilä, Antti, and Snodgrass, Colin
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We have monitored the Didymos–Dimorphos binary system in imaging polarimetric mode before and after the impact from the Double Asteroid Redirection Test mission. A previous spectropolarimetric study showed that the impact caused a dramatic drop in polarization. Our longer-term monitoring shows that the polarization of the post-impact system remains lower than the pre-impact system even months after the impact, suggesting that some fresh ejecta material remains in the system at the time of our observations, either in orbit or settled on the surface. The slope of the post-impact polarimetric curve is shallower than that of the pre-impact system, implying an increase in albedo of the system. This suggests that the ejected material is composed of smaller and possibly brighter particles than those present on the pre-impact surface of the asteroid. Our polarimetric maps show that the dust cloud ejected immediately after the impact polarizes light in a spatially uniform manner (and at a lower level than pre-impact). Later maps exhibit a gradient in polarization between the photocentre (which probes the asteroid surface) and the surrounding cloud and tail. The polarization occasionally shows some small-scale variations, the source of which is not yet clear. The polarimetric phase curve of Didymos–Dimorphos resembles that of the S-type asteroid class., Validerad;2024;Nivå 1;2024-01-29 (hanlid);Funder: STFC (ST/W001004/1); Academy of Finland (Research Council of Finland) (345115, 336546); NASA DART PS Program (80NSSC21K1131); (PID2021-123370OB-100/AEI/10.13039/501100011033/FEDER),Full text license: CC BY
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- 2024
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21. Polarimetry of Didymos–Dimorphos: Unexpected Long-term Effects of the DART Impact
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Gray, Zuri, primary, Bagnulo, Stefano, additional, Granvik, Mikael, additional, Cellino, Alberto, additional, Jones, Geraint H., additional, Kolokolova, Ludmilla, additional, Moreno, Fernando, additional, Muinonen, Karri, additional, Muñoz, Olga, additional, Opitom, Cyrielle, additional, Penttilä, Antti, additional, and Snodgrass, Colin, additional
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- 2024
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22. Comet Interceptor Mission
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Jones, Geraint H., primary, Snodgrass, Colin, additional, Tubiana, Cecilia, additional, and Küppers, Michael, additional
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- 2021
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23. In situ collection of dust grains falling from Saturn’s rings into its atmosphere
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Hsu, Hsiang-Wen, Schmidt, Jürgen, Kempf, Sascha, Postberg, Frank, Moragas-Klostermeyer, Georg, Seiß, Martin, Hoffmann, Holger, Burton, Marcia, Ye, ShengYi, Kurth, William S., Horányi, Mihály, Khawaja, Nozair, Spahn, Frank, Schirdewahn, Daniel, O’Donoghue, James, Moore, Luke, Cuzzi, Jeff, Jones, Geraint H., and Srama, Ralf
- Published
- 2018
24. The proposed Caroline ESA M3 mission to a Main Belt Comet
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Jones, Geraint H., Agarwal, Jessica, Bowles, Neil, Burchell, Mark, Coates, Andrew J., Fitzsimmons, Alan, Graps, Amara, Hsieh, Henry H., Lisse, Carey M., Lowry, Stephen C., Masters, Adam, Snodgrass, Colin, and Tubiana, Cecilia
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- 2018
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25. Titan's Magnetic Field Signature during the First Cassini Encounter
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Backes, Heiko, Neubauer, Fritz M., Dougherty, Michele K., Achilleos, Nicholas, André, Nicolas, Arridge, Christopher S., Bertucci, Cesar, Jones, Geraint H., Khurana, Krishan K., Russell, Christopher T., and Wennmacher, Alexandre
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- 2005
26. Introduction: Cometary science after Rosetta
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Jones, Geraint H., Knight, Matthew M., Fitzsimmons, Alan, and Taylor, Matt G. G. T.
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- 2017
27. Design of the EnVisS instrument optical head
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Tofani, Beatrice, primary, Gabrieli, Riccardo, additional, Impiccichè, Giuseppe, additional, Graziosi, Chiara, additional, Tommasi, Leonardo, additional, Labate, Demetrio, additional, Belli, Fabio, additional, Cicciarelli, Chiara, additional, Pernechele, Claudio, additional, Zuppella, Paola, additional, Chioetto, Paolo, additional, Nordera, Simone, additional, Jones, Geraint H., additional, Brydon, George, additional, Stankov, Anamarija, additional, Della Corte, Vincenzo, additional, and Da Deppo, Vania, additional
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- 2023
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28. Doubly Ionized Carbon Observed in the Plasma Tail of Comet Kudo-Fujikawa
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Povich, Matthew S., Raymond, John C., Jones, Geraint H., Uzzo, Michael, Ko, Yuan-Kuen, Feldman, Paul D., Smith, Peter L., Marsden, Brian G., and Woods, Thomas N.
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- 2003
29. The European Space Agency’s Comet Interceptor lies in wait
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Snodgrass, Colin and Jones, Geraint H
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- 2019
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30. Observations of a dust tail gap in comet C/2014 Q1 (PanSTARRS)
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Afghan, Qasim, primary, Jones, Geraint H., additional, Price, Oliver, additional, and Coates, Andrew, additional
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- 2023
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31. Constraints on a potential aerial biosphere on Venus: I. Cosmic rays
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Dartnell, Lewis R., Nordheim, Tom Andre, Patel, Manish R., Mason, Jonathon P., Coates, Andrew J., and Jones, Geraint H.
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- 2015
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32. A model of the spatial and size distribution of Enceladus׳ dust plume
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Meier, Patrick, Kriegel, Hendrik, Motschmann, Uwe, Schmidt, Jürgen, Spahn, Frank, Hill, Thomas W., Dong, Yaxue, and Jones, Geraint H.
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- 2014
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33. Nanodust Measurements by the Cassini Plasma Spectrometer
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Jones, Geraint H., Mann, Ingrid, editor, Meyer-Vernet, Nicole, editor, and Czechowski, Andrzej, editor
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- 2012
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34. The Science of Sungrazers, Sunskirters, and Other Near-Sun Comets
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Jones, Geraint H., Knight, Matthew M., Battams, Karl, Boice, Daniel C., Brown, John, Giordano, Silvio, Raymond, John, Snodgrass, Colin, Steckloff, Jordan K., Weissman, Paul, Fitzsimmons, Alan, Lisse, Carey, Opitom, Cyrielle, Birkett, Kimberley S., Bzowski, Maciej, Decock, Alice, Mann, Ingrid, Ramanjooloo, Yudish, and McCauley, Patrick
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- 2017
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35. Planar Structuring of Magnetic Fields at Solar Minimum and Maximum
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Jones, Geraint H., Balogh, André, and Marsden, R. G., editor
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- 2001
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36. Polarimetric analysis of STEREO observations of sungrazing kreutz comet C/2010 E6 (STEREO)
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Nežič, Rok, primary, Bagnulo, Stefano, additional, Jones, Geraint H, additional, Knight, Matthew M, additional, and Borisov, Galin, additional
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- 2022
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- View/download PDF
37. Callisto's atmosphere and its space environment: prospects for the Particle Environment Package on board JUICE
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Galli, André, primary, Vorburger, Audrey, additional, Carberry Mogan, Shane R., additional, Roussos, Elias, additional, Stenberg Wieser, Gabriella, additional, Wurz, Peter, additional, Föhn, Martina, additional, Krupp, Norbert, additional, Fränz, Markus, additional, Barabash, Stas, additional, Futaana, Yoshifumi, additional, Brandt, Pontus C., additional, Kollmann, Peter, additional, Haggerty, Dennis, additional, Jones, Geraint H., additional, Johnson, Robert E., additional, Tucker, Orenthal J., additional, Simon, Sven, additional, Tippens, Tyler, additional, and Liuzzo, Lucas, additional
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- 2022
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38. Determining the dust environment of an unknown comet for a spacecraft flyby: The case of ESA's Comet Interceptor mission
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Marschall, Raphael, Zakharov, Vladimir, Tubiana, Cecilia, Kelley, Michael S. P., van Damme, Carlos Corral, Snodgrass, Colin, Jones, Geraint H., Ivanovski, Stavro L., Postberg, Frank, Della Corte, Vincenzo, Vincent, Jean-Baptiste, Muñoz, Olga, La Forgia, Fiorangela, Levasseur-Regourd, Anny-Chantal, Comet Interceptor Team, Ministerio de Ciencia e Innovación (España), European Commission, and European Research Council
- Subjects
Earth and Planetary Astrophysics (astro-ph.EP) ,Acceleration of particles ,500 Naturwissenschaften und Mathematik::520 Astronomie::520 Astronomie und zugeordnete Wissenschaften ,FOS: Physical sciences ,Astronomy and Astrophysics ,Comets: general ,Space and Planetary Science ,astro-ph.EP ,ESA’s Comet Interceptor mission ,comets ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,astro-ph.IM ,Astrophysics - Earth and Planetary Astrophysics ,Comet interceptor - Abstract
This is an Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited., Context. An assessment of the dust environment of a comet is needed for data analysis and planning spacecraft missions, such as ESA’s Comet Interceptor (CI) mission. The distinctive feature of CI is that the target object will be defined shortly before (or even after) launch; as a result, the properties of the nucleus and dust environment are poorly constrained, and therefore make the assessment of the dust environment challenging. Aims. The main goal of the work is to provide realistic estimations of a dust environment based on very general parameters of possible target objects. Methods. Contemporary numerical models of a dusty-gas coma were used to obtain spatial distribution of dust for a given set of parameters. By varying parameters within a range of possible values, we obtained an ensemble of possible dust distributions. Then, this ensemble was statistically evaluated in order to define the most probable cases and hence reduce the dispersion. This ensemble can not only be used to estimate the likely dust abundance along a flyby trajectory of a spacecraft, for example, but also to quantify the associated uncertainty. Results. We present a methodology of the dust environment assessment for the case when the target comet is not known beforehand (or when its parameters are known with large uncertainty). We provide an assessment of dust environment for the CI mission. We find that the lack of knowledge of any particular comet results in very large uncertainties (~3 orders of magnitude) for the dust densities within the coma. The most sensitive parameters affecting the dust densities are the dust size distribution, the dust production rate, and coma brightness, often quantified by Afρ. Further, the conversion of a coma’s brightness (Afρ) to a dust production rate is poorly constrained. The dust production rate can only be estimated down to an uncertainty of ~0.5 orders of magnitude if the dust size distribution is known in addition to the Afρ. Conclusions. To accurately predict the dust environment of a poorly known comet, a statistical approach needs to be taken to properly reflect the uncertainties. This can be done by calculating an ensemble of comae covering all possible combinations within parameter space as shown in this work. © R. Marschall et al. 2022., We acknowledge the support from the International Space Science Institute (ISSI) through the team “Closing The Gap Between Ground Based And In-Situ Observations Of Cometary Dust Activity: Investigating Comet 67P To Gain A Deeper Understanding Of Other Comets”. R.M. acknowledges the support from the Swiss National Science Foundation (SNSF) under the grant P2BEP2_184482, and funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement no. 101019380). VDC acknowledges the support by the Italian Space Agency (ASI) within the ASI-INAF agreements I/032/05/0, I/024/12/0 and 2020-4-HH.0., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.
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- 2022
39. The Source of Saturn's G Ring
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Hedman, Matthew M., Burns, Joseph A., Tiscareno, Matthew S., Porco, Carolyn C., Jones, Geraint H., Roussos, Elias, Krupp, Norbert, Paranicas, Chris, and Kempf, Sascha
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- 2007
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40. Solar Wind Velocities at Comets C/2011 L4 Pan‐STARRS and C/2013 R1 Lovejoy Derived Using a New Image Analysis Technique
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Ramanjooloo, Yudish, primary and Jones, Geraint H., additional
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- 2022
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41. The in-situ exploration of Jupiter’s radiation belts
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Roussos, Elias, primary, Allanson, Oliver, additional, André, Nicolas, additional, Bertucci, Bruna, additional, Branduardi-Raymont, Graziella, additional, Clark, George, additional, Dialynas, Konstantinos, additional, Dandouras, Iannis, additional, Desai, Ravindra T., additional, Futaana, Yoshifumi, additional, Gkioulidou, Matina, additional, Jones, Geraint H., additional, Kollmann, Peter, additional, Kotova, Anna, additional, Kronberg, Elena A., additional, Krupp, Norbert, additional, Murakami, Go, additional, Nénon, Quentin, additional, Nordheim, Tom, additional, Palmaerts, Benjamin, additional, Plainaki, Christina, additional, Rae, Jonathan, additional, Santos-Costa, Daniel, additional, Sarris, Theodore, additional, Shprits, Yuri, additional, Sulaiman, Ali, additional, Woodfield, Emma, additional, Wu, Xin, additional, and Yao, Zonghua, additional
- Published
- 2021
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42. The effect of spacecraft radiation sources on electron moments from the Cassini CAPS electron spectrometer
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Arridge, Christopher S., Gilbert, Linda K., Lewis, Gethyn R., Sittler, Edward C., Jones, Geraint H., Kataria, Dhiren O., Coates, Andrew J., and Young, David T.
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- 2009
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43. The Particle Environment Package on board JUICE: What Can We Learn about Callisto's Atmosphere and Space Environment?
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Galli, André, primary, Vorburger, Audrey, additional, Carberry Mogan, Shane R., additional, Roussos, Elias, additional, Stenberg-Wieser, Gabriella, additional, Wurz, Peter, additional, Föhn, Martina, additional, Krupp, Norbert, additional, Fraenz, Markus, additional, Barabash, Stas, additional, Futaana, Yoshifumi, additional, Brandt, Pontus C., additional, Kollmann, Peter, additional, Haggerty, Dennis, additional, Jones, Geraint H., additional, Johnson, Robert E., additional, Tucker, Orenthal J., additional, Simon, Sven, additional, Tippens, Tyler F., additional, and Liuzzo, Lucas, additional
- Published
- 2021
- Full Text
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44. The dust tail gap of C/2014 Q1 (PanSTARRS)
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Afghan, Qasim, primary, Jones, Geraint H., additional, and Price, Oliver, additional
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- 2021
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- View/download PDF
45. The fisheye of the comet interceptor's EnVisS camera
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Pernechele, Claudio, primary, Da Deppo, Vania, additional, Consolaro, Luca, additional, Jones, Geraint H., additional, Brydon, George, additional, Zuppella, Paola, additional, Chioetto, Paolo, additional, Nordera, Simone, additional, Lara, Luisa Maria, additional, and Slavinskis, Andris, additional
- Published
- 2021
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46. GAUSS - genesis of asteroids and evolution of the solar system
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Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Shi, Xian, Castillo-Rogez, Julie, Hsieh, Henry, Hui, Hejiu, Ip, Wing-Huen, Lei, Hanlun, Li, Jian-Yang, Tosi, Federico, Zhou, Liyong, Agarwal, Jessica, Barucci, Antonella, Beck, Pierre, Campo Bagatin, Adriano, Capaccioni, Fabrizio, Coates, Andrew J., Cremonese, Gabriele, Duffard, René, Grande, Manuel, Jaumann, Ralf, Jones, Geraint H., Kallio, Esa, Lin, Yangting, Mousis, Olivier, Nathues, Andreas, Oberst, Jürgen, Sierks, Holger, Ulamec, Stephan, Wang, Mingyuan, The GAUSS Team, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Shi, Xian, Castillo-Rogez, Julie, Hsieh, Henry, Hui, Hejiu, Ip, Wing-Huen, Lei, Hanlun, Li, Jian-Yang, Tosi, Federico, Zhou, Liyong, Agarwal, Jessica, Barucci, Antonella, Beck, Pierre, Campo Bagatin, Adriano, Capaccioni, Fabrizio, Coates, Andrew J., Cremonese, Gabriele, Duffard, René, Grande, Manuel, Jaumann, Ralf, Jones, Geraint H., Kallio, Esa, Lin, Yangting, Mousis, Olivier, Nathues, Andreas, Oberst, Jürgen, Sierks, Holger, Ulamec, Stephan, Wang, Mingyuan, and The GAUSS Team
- Abstract
The goal of Project GAUSS (Genesis of Asteroids and evolUtion of the Solar System) is to return samples from the dwarf planet Ceres. Ceres is the most accessible candidate of ocean worlds and the largest reservoir of water in the inner Solar System. It shows active volcanism and hydrothermal activities in recent history. Recent evidence for the existence of a subsurface ocean on Ceres and the complex geochemistry suggest past habitability and even the potential for ongoing habitability. GAUSS will return samples from Ceres with the aim of answering the following top-level scientific questions: - What is the origin of Ceres and what does this imply for the origin of water and other volatiles in the inner Solar System? - What are the physical properties and internal structure of Ceres? What do they tell us about the evolutionary and aqueous alteration history of dwarf planets? - What are the astrobiological implications of Ceres? Is it still habitable today? - What are the mineralogical connections between Ceres and our current collections of carbonaceous meteorites?
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- 2021
47. AXIOM: advanced X-ray imaging of the magnetosphere
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Branduardi-Raymont, Graziella, Sembay, Steve F., Eastwood, Jonathan P., Sibeck, David G., Abbey, Tony A., Brown, Patrick, Carter, Jenny A., Carr, Chris M., Forsyth, Colin, Kataria, Dhiren, Kemble, Steve, Milan, Steve E., Owen, Chris J., Peacocke, Lisa, Read, Andy M., Coates, Andrew J., Collier, Michael R., Cowley, Stan W. H., Fazakerley, Andrew N., Fraser, George W., Jones, Geraint H., Lallement, Rosine, Lester, Mark, Porter, F. Scott, and Yeoman, Tim K.
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- 2012
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48. Uranus Pathfinder: exploring the origins and evolution of Ice Giant planets
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Arridge, Christopher S., Agnor, Craig B., André, Nicolas, Baines, Kevin H., Fletcher, Leigh N., Gautier, Daniel, Hofstadter, Mark D., Jones, Geraint H., Lamy, Laurent, Langevin, Yves, Mousis, Olivier, Nettelmann, Nadine, Russell, Christopher T., Stallard, Tom, Tiscareno, Matthew S., Tobie, Gabriel, Bacon, Andrew, Chaloner, Chris, Guest, Michael, Kemble, Steve, Peacocke, Lisa, Achilleos, Nicholas, Andert, Thomas P., Banfield, Don, Barabash, Stas, Barthelemy, Mathieu, Bertucci, Cesar, Brandt, Pontus, Cecconi, Baptiste, Chakrabarti, Supriya, Cheng, Andy F., Christensen, Ulrich, Christou, Apostolos, Coates, Andrew J., Collinson, Glyn, Cooper, John F., Courtin, Regis, Dougherty, Michele K., Ebert, Robert W., Entradas, Marta, Fazakerley, Andrew N., Fortney, Jonathan J., Galand, Marina, Gustin, Jaques, Hedman, Matthew, Helled, Ravit, Henri, Pierre, Hess, Sebastien, Holme, Richard, Karatekin, Özgur, Krupp, Norbert, Leisner, Jared, Martin-Torres, Javier, Masters, Adam, Melin, Henrik, Miller, Steve, Müller-Wodarg, Ingo, Noyelles, Benoît, Paranicas, Chris, de Pater, Imke, Pätzold, Martin, Prangé, Renée, Quémerais, Eric, Roussos, Elias, Rymer, Abigail M., Sánchez-Lavega, Agustin, Saur, Joachim, Sayanagi, Kunio M., Schenk, Paul, Schubert, Gerald, Sergis, Nick, Sohl, Frank, Sittler, Jr., Edward C., Teanby, Nick A., Tellmann, Silvia, Turtle, Elizabeth P., Vinatier, Sandrine, Wahlund, Jan-Erik, and Zarka, Philippe
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- 2012
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49. The Science of Sungrazers, Sunskirters, and Other Near-Sun Comets
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Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences, Steckloff, Jordan K., Jones, Geraint H, Knight, Matthew M, Battams, Karl, Boice, Daniel C, Brown, John, Giordano, Silvio, Raymond, John, Snodgrass, Colin, Steckloff, Jordan K, Weissman, Paul, Fitzsimmons, Alan, Lisse, Carey, Opitom, Cyrielle, Birkett, Kimberley S, Bzowski, Maciej, Decock, Alice, Mann, Ingrid, Ramanjooloo, Yudish, McCauley, Patrick, Jones, Geraint H., Knight, Matthew M., Boice, Daniel C., Birkett, Kimberley S., Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences, Steckloff, Jordan K., Jones, Geraint H, Knight, Matthew M, Battams, Karl, Boice, Daniel C, Brown, John, Giordano, Silvio, Raymond, John, Snodgrass, Colin, Steckloff, Jordan K, Weissman, Paul, Fitzsimmons, Alan, Lisse, Carey, Opitom, Cyrielle, Birkett, Kimberley S, Bzowski, Maciej, Decock, Alice, Mann, Ingrid, Ramanjooloo, Yudish, McCauley, Patrick, Jones, Geraint H., Knight, Matthew M., Boice, Daniel C., and Birkett, Kimberley S.
- Abstract
This review addresses our current understanding of comets that venture close to the Sun, and are hence exposed to much more extreme conditions than comets that are typically studied from Earth. The extreme solar heating and plasma environments that these objects encounter change many aspects of their behaviour, thus yielding valuable information on both the comets themselves that complements other data we have on primitive solar system bodies, as well as on the near-solar environment which they traverse. We propose clear definitions for these comets: We use the term near-Sun comets to encompass all objects that pass sunward of the perihelion distance of planet Mercury (0.307 AU). Sunskirters are defined as objects that pass within 33 solar radii of the Sun’s centre, equal to half of Mercury’s perihelion distance, and the commonly-used phrase sungrazers to be objects that reach perihelion within 3.45 solar radii, i.e. the fluid Roche limit. Finally, comets with orbits that intersect the solar photosphere are termed sundivers. We summarize past studies of these objects, as well as the instruments and facilities used to study them, including space-based platforms that have led to a recent revolution in the quantity and quality of relevant observations. Relevant comet populations are described, including the Kreutz, Marsden, Kracht, and Meyer groups, near-Sun asteroids, and a brief discussion of their origins. The importance of light curves and the clues they provide on cometary composition are emphasized, together with what information has been gleaned about nucleus parameters, including the sizes and masses of objects and their families, and their tensile strengths. The physical processes occurring at these objects are considered in some detail, including the disruption of nuclei, sublimation, and ionisation, and we consider the mass, momentum, and energy loss of comets in the corona and those that venture to lower altitudes. The different components of comae and tail
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- 2018
50. Telecentric F-theta fisheye lens for space applications
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Pernechele, Claudio, primary, Consolaro, Luca, additional, Jones, Geraint H., additional, Brydon, George, additional, and Da Deppo, Vania, additional
- Published
- 2021
- Full Text
- View/download PDF
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