Search Publications
Spectral properties of lunar impact melt deposits from Moon Mineralogy Mapper (M3) data
Tornabene, L. L.; Neish, C. D.; Cannon, K. M. +3 more
Lunar impact melt deposits have unusual surface properties, unlike any measured terrestrial lava flow. Radar observations suggest that they are incredibly rough at decimeter scales, but they appear smooth in high-resolution, meter-scale optical images. The cause of their unusual surface roughness is unknown. In this work, we investigate the proper…
Landforms indicative of regional warm based glaciation, Phlegra Montes, Mars
Butcher, Frances E. G.; Gallagher, Colman; Balme, Matt +2 more
Viscous flow features (VFF) occur in the mid-latitudes of Mars and have characteristics consistent with being glaciers. Climate models suggest that martian glaciers are cold-based systems in which meltwater has never been widely produced. VFF are common in Phlegra Montes, a mountain range in the mid-latitudes of the northern hemisphere of Mars. Ho…
Daily dust variation from the PFS MEx observations
Giuranna, Marco; Wolkenberg, Paulina
We collected over 7 Martian years (MY) of data observed by the Planetary Fourier Spectrometer (PFS) to present a daily variation of dust content in the Martian atmosphere. We found three typical behaviors of dust opacities with LT (local time). The most peculiar variation was observed when global dust storms (MYs 28 and 34) or particularly strong …
Monitoring the negative polarization in Comet 29P/Schwassmann-Wachmann during quiescence
Kim, Sungsoo S.; Videen, Gorden; Zubko, Evgenij +4 more
During five nights between February 3 and 10, 2021, we monitored the degree of linear polarization in Comet 29P/Schwassmann-Wachmann with the broadband R filter. It is the first polarimetric investigation of this comet measured during a period of quiescent activity. We found a nearly constant negative polarization PQ ≈ -2.1% at α ≈ 9.5°…
Impact of gradients at the martian terminator on the retrieval of ozone from SPICAM/MEx
Aoki, S.; Vandaele, A. C.; Daerden, F. +11 more
Rapid variations of pressure, temperature and illumination at the day-night terminator have the potential to cause asymmetries in the abundance distribution of the atmosphere constituents along the line of sight (LOS) of a solar occultation experiment. Ozone, in particular, displays steep density gradients across the terminator of Mars due to phot…
High-fidelity comet 67P ephemeris and predictions based on Rosetta data
Weryk, Robert; Farnocchia, Davide; Micheli, Marco +2 more
Because of observational biases and outgassing, comets are notoriously challenging in terms of trajectory estimation and ephemeris predictions. We used tracking data collected by ESA's Rosetta mission at 67P/Churyumov-Gerasimenko to derive 10-m level constraints on the distance between the Earth and 67P in 2014 and 2016, which, together with high-…
CO2 retrievals in the Mars daylight thermosphere from its 4.3 µm limb emission measured by OMEGA/MEx
Bibring, Jean-Pierre; Gondet, Brigitte; Funke, Bernd +6 more
We present a non-local thermodynamic equilibrium retrieval scheme for atmospheric composition and its application to Mars CO2 infrared limb emissions as measured by the OMEGA instrument on board Mars Express (MEx). These emissions are caused by CO2 fluorescence of solar radiation, and thus the retrieval scheme accounts for no…
Simultaneous sublimation activity of primitive asteroids including (24) Themis and (449) Hamburga: Spectral signs of an exosphere and the solar activity impact
Petrova, Elena V.; Busarev, Vladimir V.; Irsmambetova, Tatiana R. +2 more
We describe and analyze simultaneous sublimation activity of the main-belt primitive asteroids during their perihelion passages, which was detected by spectral methods. This phenomenon was observed for the first time in September 2012 for asteroids (145) Adeona, (704) Interamnia, (779) Nina, and Mars-crosser (1474) Beira (Busarev et al., 2015, 201…
Kronoseismology V: A panoply of waves in Saturn's C ring driven by high-order internal planetary oscillations
Nicholson, Philip D.; French, Richard G.; Hedman, Matthew M. +3 more
Saturn's rings act as a system of innumerable test particles that are remarkably sensitive to periodic disturbances in the planet's gravitational field. We identify 15 additional density and bending waves in Saturn's C ring driven by the planet's internal normal mode oscillations. The collective response of the rings to Saturn's oscillations resul…
Geology and history of the Malea Planum region: A new view of Mars' oldest large volcanic province
Williams, David A.; Bernhardt, Hannes
Characterized by large paterae and late Noachian wrinkle-ridged plains, the ~1.2 million km2 Malea Planum region (MPR) has been grouped into a circum-Hellas volcanic province and likely represents the oldest of the large volcanic areas on Mars. Being key to Mars' early volcanic, tectonic, and climate evolution, we conducted a comprehens…