Search Publications
New astrometric positions of the Jovian irregular satellites Elara and Pasiphae in 2016-2018
Cheng, X.; Zhang, H. Y.; Yan, D. +5 more
A total of 372 astrometric positions of Jovian irregular satellites Elara and Pasiphae were obtained during three successive oppositions in 2016, 2017, and 2018, by 1 m telescope at Yunnan Observatory. Based on Gaia DR2 catalogue, 196 new positions of Elara and 176 new positions of Pasiphae were collected. We compared our observations to the theor…
Size of the smallest particles in Saturn's rings
Kimura, Hiroshi; Ohtsuki, Keiji; Hirata, Naoyuki +2 more
Spacecraft and ground-based observations have shown that particles in Saturn's main rings have a power-law distribution roughly between centimeter and ten meters, but sub-centimeter particles appear to be lacking. Recent studies based on Cassini observations suggest that the minimum particle size is on the order of millimeters, although their abun…
A photochemical model of ultraviolet atomic line emissions in the inner coma of comet 67P/Churyumov-Gerasimenko
Bhardwaj, Anil; Raghuram, Susarla
Alice ultraviolet spectrometer onboard Rosetta space mission observed several spectroscopic emissions emanated from volatile species of comet 67P/Churyumov-Gerasimenko (hearafter 67P/C-G) during its entire escorting phase. The measured emission intensities, when the comet was at around 3 AU pre-perihelion, have been used to derive electron densiti…
Titan's gravity field and interior structure after Cassini
Iess, L.; Durante, Daniele; Hemingway, D. J. +2 more
Since its arrival at Saturn in 2004, Cassini performed nine flybys devoted to the determination of Titan's gravity field and its tidal variations. Here we present an updated gravity solution based on the final data set collected during the gravity-dedicated passes, before Cassini's plunge into Saturn's atmosphere. The data set includes an addition…
Probable detection of hydrogen sulphide (H2S) in Neptune's atmosphere
Fletcher, Leigh N.; Bézard, Bruno; Irwin, Patrick G. J. +4 more
Recent analysis of Gemini-North/NIFS H-band (1.45-1.8 µm) observations of Uranus, recorded in 2010, with recently updated line data has revealed the spectral signature of hydrogen sulphide (H2S) in Uranus's atmosphere (Irwin et al., 2018). Here, we extend this analysis to Gemini-North/NIFS observations of Neptune recorded in 2009 …
Mars atmospheric chemistry simulations with the GEM-Mars general circulation model
Daerden, F.; Neary, L.; Viscardy, S. +5 more
General Circulation Models with interactive physical and chemistry processes are the state-of-the-art tools for an integrated view and understanding of the Martian atmosphere and climate system. The GEM-Mars model currently includes 16 tracers for chemical composition and applies a fully online, interactive calculation of the photo- and gas phase …
Jupiter's ammonia distribution derived from VLA maps at 3-37 GHz
de Pater, Imke; Sault, R. J.; Wong, Michael H. +3 more
We observed Jupiter four times over a full rotation (10 h) with the upgraded Karl G. Jansky Very Large Array (VLA) between December 2013 and December 2014. Preliminary results at 4-17 GHz were presented in de Pater et al. (2016); in the present paper we present the full data set at frequencies between 3 and 37 GHz. Major findings are:
i) The …Mutual orbit orientations of transneptunian binaries
Buie, M. W.; Roe, H. G.; Trujillo, C. A. +8 more
We present Keplerian orbit solutions for the mutual orbits of 17 transneptunian binary systems (TNBs). For ten of them, the orbit had not previously been known: 60458 2000 CM114, 119979 2002 WC19, 160091 2000 OL67, 160256 2002 PD149, 469514 2003 QA91, 469705 ǂKá̦gára, 508788 2000 CQ114
A survey of water production in 61 comets from SOHO/SWAN observations of hydrogen Lyman-alpha: Twenty-one years 1996-2016
Bertaux, J. -L.; Combi, M. R.; Quémerais, E. +2 more
The Solar Wind Anisotropies (SWAN) instrument on the SOlar and Heliospheric Observatory (SOHO) satellite has observed 44 long period and new Oort cloud comets and 36 apparitions of 17 short period comets since its launch in December 1995. Water production rates have been determined from the over 3700 images producing a consistent set of activity v…
Olivine-dominated A-type asteroids in the main belt: Distribution, abundance and relation to families
Hsieh, Henry H.; Moskovitz, Nicholas A.; Polishook, David +5 more
Differentiated asteroids are rare in the main asteroid belt despite evidence for ∼ 100 distinct differentiated bodies in the meteorite record. We have sought to understand why so few main-belt asteroids differentiated and where those differentiated bodies or fragments reside. Using the Sloan Digital Sky Survey (SDSS) to search for a needle in a ha…