Search Publications
New astrometric positions for six Jovian irregular satellites using Gaia DR3 in 2016 — 2021
Vienne, A.; Lin, F. R.; Peng, Q. Y. +2 more
The Jovian system is like a miniature solar system, with the system being more than twice as massive as all the other planets combined and having many natural satellites. Its formation and early evolution had a profound influence on our knowledge of the sculpting of the architecture of the solar system. Astrometric observations are of importance, …
Rotation period estimates for 14 asteroids with the Earth MOID less than 1.1 AU
Eglitis, Ilgmars; Svincicka, Darja
In the present study, the Lomb–Scargle Scargle (L–S) method was employed for the analysis of brightness measurements from multiple observatories as published in the Minor Planet Center (MPC) circulars, as well as brightness measurements from the Baldone Observatory, to determine the periods of asteroids. The periods of fifteen asteroids were deter…
A global colour mosaic of Mars from Mars Express HRSC high altitude observations
Jaumann, R.; Postberg, F.; Matz, K. -D. +8 more
The ever-changing transparency of the Martian atmosphere hinders the determination of absolute surface colour from spacecraft images. While individual high-resolution images from low orbit reveal numerous colour details of the geology, the colour variation between images caused by scattering off atmospheric dust can easily be of greater magnitude.…
NAROO program: Analysis of USNO Galilean observations 1967–1998
Lainey, V.; Robert, V.; Arlot, J. -E. +1 more
The New Astrometric Reduction of Old Observations (NAROO) program is dedicated to the measurement of astrophotographic plates and the analysis of old observations for scientific purposes. One of the main objectives of the NAROO program is to provide accurate positional measurements of planets and satellites to improve our knowledge of their orbits…
Surface activity of H2 2
Tenishev, Valeriy; Fougere, Nicolas; Combi, Michael +3 more
On November 4, 2010, the EPOXI extended the mission of the Deep Impact spacecraft, flew by comet 103P/Hartley 2, and made a series of spectral images in both the infrared and the visible. The High-Resolution Instrument Infrared Spectrometer (HRI-IR) observed the comet and its surrounding coma, enabling maps in the light of the infrared emissions o…
A conceptual model for the formation of ramparts on Martian impact crater ejecta
Boyce, Joseph M.; Mouginis-Mark, Peter J.
Mars Orbiter Laser Altimeter (MOLA) elevation measurements for 23 different impact craters and 12 different long runout landslides show rampart ridges on Martian fluidized ejecta flows are higher relief than those on Martian landslides. We propose a conceptual model to explain this height difference that is based on the effects of the impact and e…
A modeling approach for water and sediment transport in Jezero crater on Mars based on new geomorphological evidence
Postberg, Frank; Jaumann, Ralf; Gross, Christoph +3 more
In our study we examined water-related processes and events in the Jezero crater on Mars using flow discharge and sediment transport models of: 1) the western inlet valley carving, 2) the northern inlet valley carving, 3) crater flooding by only northern inlet and 4) by both northern and western inlets, 5) erosion of the western rim by the western…
Magnetosonic waves in the Martian ionosphere driven by upstream proton cyclotron waves: Two-point observations by MAVEN and Mars Express
Halekas, J. S.; Fowler, C. M.; Collinson, G. +5 more
Recent observations from the Mars Atmosphere and Volatile EvolutioN (MAVEN) and Mars Express (MEX) spacecraft have suggested that pressure pulses originating from upstream proton cyclotron waves (PCWs) can "ring" the Martian magnetopause at the same frequency and drive magnetosonic waves in the upper ionosphere of Mars, thereby transporting energy…
Quantifying lava surface heterogeneity on Mars using THEMIS brightness temperature data
Ramsey, M. S.; McKeeby, B. E.; Peterson, T.
The analysis and characterization of any planetary surface relies heavily on orbital data. The Martian surface is dominated by extrusive volcanism with most of the younger rocks being either too rough or at altitudes that are commonly inaccessible to landers or rovers. Therefore, the accurate interpretation of orbital data is critical to understan…
Martian Chaos terrain fracture geometry indicates drainage and compaction of laterally heterogeneous confined aquifers
Levy, Joseph S.; Subak, Thomas F.; Armstrong, Ian +7 more
The interlocking plateaus of martian chaotic terrain have long been inferred to relate to Hesperian outflow-channel megafloods. Numerous hypotheses have been invoked to explain the formation of the hundreds-of-kilometer-scale depressions that chaoses are found in, and the mechanisms by which the fractures formed. Hypotheses range from mechanisms i…