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The digital global geologic map of Mars: Chronostratigraphic ages, topographic and crater morphologic characteristics, and updated resurfacing history
Hare, T. M.; Tanaka, K. L.; Robbins, S. J. +2 more
A new global geologic map of Mars has been completed in a digital, geographic information system (GIS) format using geospatially controlled altimetry and image data sets. The map reconstructs the geologic history of Mars, which includes many new findings collated in the quarter century since the previous, Viking-based global maps were published, a…
Phobos' shape and topography models
Shi, X.; Oberst, J.; Willner, K.
The global shape and the dynamic environment are fundamental properties of a body. Other properties such as volume, bulk density, and models for the dynamic environment can subsequently be computed based on such models. Stereo-photogrammetric methods were applied to derive a global digital terrain model (DTM) with 100 m/pixel resolution using High…
Hot oxygen and carbon escape from the martian atmosphere
Lammer, H.; Shematovich, V. I.; Lichtenegger, H. +1 more
The escape of hot O and C atoms from the present martian atmosphere during low and high solar activity conditions has been studied with a Monte-Carlo model. The model includes the initial energy distribution of hot atoms, elastic, inelastic, and quenching collisions between the suprathermal atoms and the ambient cooler neutral atmosphere, and appl…
The surface geology and geomorphology of Phobos
Head, J. W.; Basilevsky, A. T.; Zubarev, A. E. +3 more
The martian moon Phobos is 26 km×22.8 km×18.2 km in size, and the major landforms on its surface are craters and grooves. We analyzed the visible craters on the surface of Phobos where ~1300 craters≥200 m in diameter, ~70 craters≥1 km, and ~30 craters≥2 km are identified; Stickney, the largest crater on Phobos, is about 8 km in diameter. Most crat…
Martian satellite orbits and ephemerides
Lainey, V.; Jacobson, R. A.
We discuss the general characteristics of the orbits of the Martian satellites, Phobos and Deimos. We provide a concise review of the various descriptions of the orbits by both analytical theories and direct numerical integrations of their equations of motion. After summarizing the observational data used to determine the orbits, we discuss the re…
Mars Express investigations of Phobos and Deimos
Bibring, J. -P.; Gondet, B.; Barabash, S. +39 more
The Mars Express mission was launched in June 2003 and was inserted into orbit around Mars in December 2003. Its main objective is to study the Mars' subsurface, surface, atmosphere and interaction with the solar wind. A secondary objective is to study the martian moons, in particular the largest one Phobos, thanks to a near polar and elliptical o…
Amazonian mid- to high-latitude glaciation on Mars: Supply-limited ice sources, ice accumulation patterns, and concentric crater fill glacial flow and ice sequestration
Head, James W.; Fastook, James L.
Concentric crater fill (CCF) occurs in the interior of impact craters in mid- to high latitudes on Mars and is interpreted to have formed by glacial ice flow and debris covering. We use the characteristics and orientation of deposits comprising CCF, the thickness of pedestal deposits in mid- to high-latitude pedestal craters (Pd), the volumes of t…
Composition of Surface Materials on the Moons of Mars
Thomas, Nicolas; Pieters, Carle M.; Murchie, Scott +1 more
The two small asteroid-like bodies orbiting Mars, Phobos and Deimos, are low albedo and exhibit similar visible to near-infrared spectra. Determining the origin of these moons is closely tied to determining their composition. From available spectroscopic data Phobos exhibits two distinct types of materials across its surface, and data from both Ma…
Mapping the wavelength position of deepest absorption features to explore mineral diversity in hyperspectral images
van Ruitenbeek, Frank J. A.; Bakker, Wim H.; van der Werff, Harald M. A. +5 more
A new method is presented for the exploratory analysis of hyperspectral OMEGA imagery of Mars. It involves mapping the wavelength position and depth of the deepest absorption feature in the range between 2.1 and 2.4 µm, where reflectance spectra of minerals such as phyllosilicates, carbonates and sulphates contain diagnostic absorption featu…
A cold hydrological system in Gale crater, Mars
McKay, Christopher P.; Squyres, Steven W.; Clifford, Stephen M. +9 more
Gale crater is a ~154-km-diameter impact crater formed during the Late Noachian/Early Hesperian at the dichotomy boundary on Mars. Here we describe potential evidence for ancient glacial, periglacial and fluvial (including glacio-fluvial) activity within Gale crater, and the former presence of ground ice and lakes. Our interpretations are derived …