Search Publications
Calibration of the NOMAD-UVIS data
Vandaele, Ann Carine; Neefs, Eddy; Aoki, Shohei +23 more
The Ultraviolet and VIsible Spectrometer (UVIS), covering the 200-650 nm range, is one of three spectrometers that comprise the NOMAD instrument on the ExoMars 2016 Trace Gas Orbiter (TGO). UVIS can operate in solar occultation, nadir and limb viewing mode and was designed to monitor ozone and aerosols in the Martian atmosphere. Here, we describe …
Multiband photometry of Martian Recurring Slope Lineae (RSL) and dust-removed features at Horowitz crater, Mars from TGO/CaSSIS color observations
Pajola, M.; Cremonese, G.; Thomas, N. +12 more
Recurring Slope Lineae (RSL) are narrow, dark streaks typically lengthening down Martian steep slopes during warm seasons, fading during the cold ones and regularly recurring every Martian year. Their origin is still debated. Although initially interpreted as possible flows of seeping water, either coming from a subsurface aquifer or through atmos…
Water vapor saturation and ice cloud occurrence in the atmosphere of Mars
Vandaele, Ann Carine; Aoki, Shohei; Kleinböhl, Armin +3 more
We investigate water vapor saturation in the martian atmosphere in the presence or proximity of water ice clouds. We evaluate mixing ratio profiles of ambient water vapor derived from measurements by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) and the Nadir and Occultation for MArs Discovery (NOMAD) instrument in comparison wi…
A CaSSIS and HiRISE map of the Clay-bearing Unit at the ExoMars 2022 landing site in Oxia Planum
Quantin-Nataf, Cathy; Pajola, Maurizio; Cremonese, Gabriele +8 more
In preparation for the operations of the ExoMars Rosalind Franklin rover, characterising its landing site in Oxia Planum is essential. Of particular interest is the extensive Clay-bearing Unit present at the site, a key target in the search for biosignatures. In this paper we provide a map based on variations in colour and spectral information wit…
Absolute calibration of the Colour and Stereo Surface Imaging System (CaSSIS)
Almeida, Miguel; Cremonese, Gabriele; Thomas, Nicolas +5 more
The Colour and Stereo Surface Imaging System (CaSSIS) onboard the ExoMars Trace Gas Orbiter (TGO) has observed several standard stars and Jupiter with the aim of deriving the absolute calibration factors that convert observed signal into reflectance ("I over F"). The targets were observed through all four colour filters and hence a relative calibr…
Automated Crater detection from Co-registered optical images, elevation maps and slope maps using deep learning
Tewari, Atal; Verma, Vinay; Srivastava, Pradeep +2 more
Craters are topographic structures resulting from impactors striking the surface of planetary bodies. This paper proposes a novel way of simultaneously utilizing optical images, digital elevation maps (DEMs), and slope maps for automatic crater detection on the lunar surface. The proposed system utilizes Mask R-CNN by tuning it for the crater dete…
The five largest satellites of Uranus: Astrometric observations spread over 29 years at the Pico dos Dias Observatory
Fienga, A.; Assafin, M.; Camargo, J. I. B. +2 more
We present the astrometry of the five largest satellites of Uranus from observations spread over almost three decades with photographic plates and CCDs (mainly), taken at the Pico dos Dias Observatory - Brazil. All positions presented here are obtained from the reanalysis of measurements and images used in previous publications. Reference stars ar…
Prospects for mapping temporal height variations of the seasonal CO2 snow/ice caps at the Martian poles by co-registration of MOLA profiles
Oberst, Jürgen; Schmidt, Frédéric; Steinbrügge, Gregor +3 more
We investigate the feasibility and demonstrate the merits of using Mars Orbiter Laser Altimeter (MOLA) profiles to retrieve seasonal height variations of CO2 snow/ice cap in Mars' polar areas by applying a co-registration strategy. We present a prototype analysis on the research region of [85.75°S, 86.25°S, 300°E, 330°E] that is located…
Geology, in-situ resource-identification and engineering analysis of the Vernal crater area (Arabia Terra): A suitable Mars human landing site candidate
Pajola, M.; Cremonese, G.; Thomas, N. +15 more
A multidisciplinary study of an ancient area of Mars (Early to Late Noachian) located in Arabia Terra is presented, centred at 6°1′N, 354°54′ E and including the 55 km size Vernal crater. By means of different spatial scale imagery datasets and digital terrain models (MOLA, THEMIS, HRSC, CTX, CaSSIS and HiRISE), we prepare a high-resolution geolog…
CaSSIS-based stereo products for Mars after three years in orbit
Mège, Daniel; Pajola, Maurizio; Cremonese, Gabriele +10 more
The Colour and Stereo Surface Imaging System (CaSSIS) on board the ExoMars Trace Gas Orbiter (TGO), operating in push-frame mode, provides multiband images at four different wavelengths thanks to a Filter Strip Assembly with a panchromatic filter and three broadband filters within the visible and near infrared range. The camera acquires stereo pai…