Search Publications
Retrieving cloud, dust and ozone abundances in the Martian atmosphere using SPICAM/UV nadir spectra
Vandaele, A. C.; Montmessin, F.; Willame, Y. +4 more
We present the retrieval algorithm developed to analyse nadir spectra from SPICAM/UV aboard Mars-Express. The purpose is to retrieve simultaneously several parameters of the Martian atmosphere and surface: the dust optical depth, the ozone total column, the cloud opacity and the surface albedo. The retrieval code couples the use of an existing com…
Idunn Mons on Venus: Location and extent of recently active lava flows
Helbert, Jörn; D'Incecco, Piero; D'Amore, Mario +1 more
From 2006 until 2014 the ESA Venus Express probe observed the atmosphere and surface of the Earth's twin planet. The Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) has provided data that indicate the occurrence of recent volcanic activity on Venus. We selected the eastern flank of Idunn Mons - Imdr Regio's single large volcano - as the…
Sensitivity and fragmentation calibration of the time-of-flight mass spectrometer RTOF on board ESA's Rosetta mission
Mall, Urs; Fiethe, Björn; Wurz, Peter +8 more
The European Space Agency's Rosetta spacecraft, with the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) onboard, has been following and observing comet 67P/Churyumov-Gerasimenko since summer 2014. Prior to this period, and due to a technical failure also during this period, optimization and calibration campaigns have been condu…
New constraints on Ganymede's hydrogen corona: Analysis of Lyman-α emissions observed by HST/STIS between 1998 and 2014
Alday, Juan; Saur, Joachim; Roth, Lorenz +4 more
Far-ultraviolet observations of Ganymede's atmospheric emissions were obtained with the Space Telescope Imaging Spectrograph (STIS) onboard of the Hubble Space Telescope (HST) on several occasions between 1998 and 2014. We analyze the Lyman-α emission from four HST campaigns in order to constrain the abundance and variation of atomic hydrogen in G…
Ultra low frequency waves at Venus: Observations by the Venus Express spacecraft
Fränz, M.; Zhang, T. L.; Dubinin, E. +2 more
The generation of waves with low frequencies (below 100 mHz) has been observed in the environment of most bodies in the solar system and well studied at Earth. These waves can be generated either upstream of the body in the solar wind by ionization of planetary exospheres or ions reflected from a bow shock or in the magnetosheath closer to the mag…
Bidirectional reflectance and VIS-NIR spectroscopy of cometary analogues under simulated space conditions
Thomas, Nicolas; Fornasier, Sonia; Pommerol, Antoine +7 more
This work is intended to be the second publication in a series of papers reporting on the spectro-photometric properties of cometary analogues measured in the laboratory. Herein, we provide in-situ hyperspectral imaging data in the 0.40-2.35 µm range from three sublimation experiments under simulated space conditions in thermal vacuum from s…
Measurement of dust optical depth using the solar irradiance sensor (SIS) onboard the ExoMars 2016 EDM
Rannou, P.; Toledo, D.; Gómez, L. +5 more
The solar irradiance sensor (SIS) was included in the DREAMS package onboard the ExoMars 2016 Entry Descent and Landing Demonstrator Module, and has been selected in the METEO meteorological station onboard the ExoMars 2020 Lander. This instrument is designed to measure at different time intervals the scattered flux or the sum of direct flux and s…
Bidirectional reflectance of laboratory cometary analogues to interpret the spectrophotometric properties of the nucleus of comet 67P/Churyumov-Gerasimenko
Thomas, Nicolas; Fornasier, Sonia; Pommerol, Antoine +5 more
In this work we provide measurements of the bidirectional reflectance in the VIS-NIR spectral range for a selection of laboratory samples to deduce parameters such as their visible spectrum, phase curve, hemispheric albedo and phase reddening. The aim is to simulate the reflectance of the comet nucleus in order to aid the interpretation of data fr…
The Stickney Crater ejecta secondary impact crater spike on Phobos: Implications for the age of Stickney and the surface of Phobos
Head, James W.; Ramsley, Kenneth R.
A global and uniformly distributed spike of secondary impact craters on Phobos with diameters (D) <0.6 km and a portion of craters up to D 2 km were produced by Stickney Crater ejecta, including secondary craters within the surface area of Stickney Crater. The global exposure of Phobos to Stickney secondary impacts was facilitated by the desync…
Martian ionosphere observed by Mars Express. 2. Influence of solar irradiance on upper ionosphere and escape fluxes
Barabash, S.; Pätzold, M.; Dubinin, E. +4 more
We present multi-instrument observations of the effects of solar irradiance on the upper Martian ionosphere and escape fluxes based on Mars Express measurements obtained over almost 12 years. It is shown that the variations in the upper ionosphere caused by solar irradiance lead to significant changes in the trans-terminator fluxes of low-energy i…