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October 1985 - present
October 1985 - present
Publications
Publications (392)
Perseverance explored two geological units on the floor of Jezero Crater over the first 420 Martian days of the Mars2020 mission. These units, the Máaz and Séítah formations, are interpreted to be igneous in origin, with traces of alteration. We report the detection of carbonate phases along the rover traverse based on laser-induced breakdown spect...
Askival is a light‐toned, coarsely crystalline float rock, which was identified near the base of Vera Rubin Ridge in Gale crater. We have studied Askival, principally with the ChemCam instrument but also using APXS compositional data and MAHLI images. Askival and an earlier identified sample, Bindi, represent two rare examples of feldspathic cumula...
Plain Language Summary
The study of Martian soils is of considerable interest as the nature of the mineral phases they contain, formed by the action of water for some of them, can give information on the past environments of the planet. Mineralogical analyses in Gale crater have shown that about one third of soils are composed of poorly crystalline...
jats:p>The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater’s sedimentary delta, finding that the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich roc...
The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater’s sedimentary delta, finding the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich rock, which acc...
Before Perseverance, Jezero crater's floor was variably hypothesized to have a lacustrine, lava, volcanic airfall, or aeolian origin. SuperCam observations in the first 286 Mars days on Mars revealed a volcanic and intrusive terrain with compositional and density stratification. The dominant lithology along the traverse is basaltic, with plagioclas...
We examine the observed properties of the Nili Fossae olivine-clay-carbonate lithology from orbital data and in situ by the Mars 2020 rover at the S\'e\'itah unit in Jezero crater, including: 1) composition (Liu, 2022) 2) grain size (Tice, 2022) 3) inferred viscosity (calculated based on geochemistry collected by SuperCam (Wiens, 2022)). Based on t...
Prior to the Perseverance rover landing, the acoustic environment of Mars was unknown. Models predicted that: (i) atmospheric turbulence changes at centimeter scales or smaller at the point where molecular viscosity converts kinetic energy into heat1, (ii) the speed of sound varies at the surface with frequency2,3, and (iii) high frequency waves ar...
Visible-shortwave infrared (VSWIR) imaging spectrometers map composition remotely with spatial context, typically at many meters-scale from orbital and airborne data. Here, we evaluate VSWIR imaging spectroscopy capabilities at centimeters to sub-millimeter scale at the Samail Ophiolite, Oman, where mafic and ultramafic lithologies and their altera...
Carbonate minerals have been detected in Jezero crater, an ancient lake basin that is the landing site of the Mars 2020 Perseverance rover, and within the regional olivine-bearing (ROB) unit in the Nili Fossae region surrounding this crater. It has been suggested that some carbonates in the margin fractured unit, a rock unit within Jezero crater, f...
The behavior of the three primary olivine absorptions near 1 μm (referred to as M1-1, M2, M1-2) is revisited by means of an advanced version of MGM analysis. The (M1-1, M2, M1-2) band center positions are used simultaneously to produce a constrained prediction across an extended range Fo#[0–90] of olivine solid solution composition. The established...
The Curiosity rover has been characterizing mineralogical and chemical compositions of Gale crater soils on Mars since 2012. Given its sub-millimeter scale of analysis, the ChemCam instrument is well suited to study the composition of soil constituents. However, the interpretation of LIBS data on soils in the martian environment is complicated by t...
On the NASA 2020 rover mission to Jezero crater, the remote determination of the texture, mineralogy and chemistry of rocks is essential to quickly and thoroughly characterize an area and to optimize the selection of samples for return to Earth. As part of the Perseverance payload, SuperCam is a suite of five techniques that provide critical and co...
The ChemCam Remote Micro-Imager (RMI) onboard Curiosity was originally designed to document the tiny areas analyzed by the instrument’s laser-induced breakdown spectroscopy (LIBS) tech-nique on rocks within a few meters around the rover [1, 2]. The RMI produces 1024x1024 pixel black and white images directly from ChemCam’s telescope focal plane. Ea...
Gale crater preserves a 5-km-thick sequence of stratified rocks, the lower-most section of which exhibits orbital spectra signatures of clay miner-als transitioning up to sulfates over several hundred me-ters of stratigraphy [1,2]. Understanding the reason for this wet-to-dry change recorded in the mineralogical signature is one of the primary obje...
Much of our knowledge about the history and evolution of the Moon stems from orbital and laboratory analyses of volcanic materials. Pyroclastics are our best source of information about lunar mantle composition and mineralogy, P/T conditions, and volatiles in the interior. The volatiles in pyroclastic glasses are also relevant for in situ resource...
The SuperCam instrument suite provides the Mars 2020 rover, Perseverance, with a number of versatile remote-sensing techniques that can be used at long distance as well as within the robotic-arm workspace. These include laser-induced breakdown spectroscopy (LIBS), remote time-resolved Raman and luminescence spectroscopies, and visible and infrared...
Von Kármán crater's floor was flooded with mare basalts during the Imbrian period. This site is the target of China's ongoing Chang'e-4 mission that includes the Yutu-2 rover and its instrumental payload. The Zhinyu crater, one of the largest craters within a few tens of kilometers from the landing site, is the product of a fresh impact that excava...
Gale crater is a large impact crater with a ca 5 km thick sequence of stratified rocks in it, expressed today as a central eroded mound (i.e., Aeolis Mons informally named Mt. Sharp). A goal of the current Mars Science Laboratory mission in Gale crater is to investigate the processes that deposited, lithified, and eroded this fill. The Light-Toned...
Visible/short‐wave infrared spectral data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) show absorptions attributed to hematite at Vera Rubin ridge (VRR), a topographic feature on northwest Mt. Sharp. The goals of this study are to determine why absorptions caused by ferric iron are strongly visible from orbit at VRR, and to...
We investigate the performance of the recently released image processing software suite “Topaz Gigapixel” on martian images from the Mars Science Laboratory “Curiosity” rover. The objective is to evaluate the possibility to visually enhance the apparent resolution of acquired images, using cutting-edge image processing algorithms, in order to impro...
PaSSTEL (PlanetAry Surface Spectroscopy Toulouse Experimental Laboratory) database is aimed at characterizing the optical response of geological targets from 10 mm x 10 mm to 20 cm x 20 cm size, ranging from controlled powders to complex slab rock samples.
These data are used for testing and improving spectral deconvolution and spectrophotometric...
The Curiosity Rover of Mars Science Laboratory has identified igneous float rocks in Gale Crater which offer new insights about the differentiation of the martian lithosphere. Here we describe likely origins for some unique Gale plutonic and cumulate rocks and compare to the martian meteorites. At the Ireson Hill locality around sol 1606 a group of...
An in situ investigation on the far side of the Moon has identified materials that might have originated from the lunar mantle. The results could lead to improved models of how the Moon formed and evolved. Spectral observations of the far side of the Moon.
This study presents an inventory of possible chemical reactions affecting, or having affected, the Venus surface. Fluid rock reactions are simulated using experiments under conditions close to the present surface. Slabs or powder of several natural and synthetic silicate material (crystalline fresh basalt, altered basalt, obsidian, pumice and basal...
As part of the Phase 2 Bagnold Dune campaign at Gale Crater, Mars, constraints on the geochemistry, mineralogy, and oxidation state of pristine and disturbed linear sand ripples were made using visible/near‐infrared spectral observations for comparison to Phase 1 spectra of the barchan dunes to the north. Spectra acquired by the ChemCam and Mastcam...
Neukum Crater, located at about 28°E/45°S at Noachis Terra on Mars, contains various geomorphological features that indicate a diverse geological history forming the crater during the past up to 4 Ga years. Most prominent features of this 102 km-crater are the large dark dune field and the two pits on its floor. The basaltic composition of the dune...
The Curiosity rover conducted the first field investigation of an active extraterrestrial dune. This study of the Bagnold dunes focuses on the ChemCam chemical results and also presents findings on the grain size distributions based on the ChemCam RMI and MAHLI images. These active dunes are composed of grains that are mostly <250 μm. Their composi...
The Mars Science Laboratory Curiosity rover performed coordinated measurements to examine the textures and compositions of aeolian sands in the active Bagnold dune field. The Bagnold sands are rounded to subrounded, very fine- to medium- sized (~45-500 µm) with ≥6 distinct grain colors. In contrast to sands examined by Curiosity in a dust-covered,...
As part of the Bagnold Dune campaign conducted by Mars Science Laboratory rover Curiosity, visible/near-infrared reflectance spectra of dune sands were acquired using Mast Camera (Mastcam) multispectral imaging (445-1013 nm) and Chemistry and Camera (ChemCam) passive point spectroscopy (400-840 nm). By comparing spectra from pristine and rover-dist...
Determining which petrological processes build the mantle-crust dunitic transition zone (DTZ) in oceanic spreading settings has a direct impact on our understanding of thermal and chemical transfers on Earth. We report on understated but widespread mineral assemblages present in the DTZ at the top of a mantle diapir (Oman ophiolite), including parg...
Until recently, Mars was considered a basalt-covered world, but this vision is evolving thanks to new orbital, in situ and meteorite observations, in particular of rocks of the ancient Noachian period. In this contribution we summarize newly recognized compositional and mineralogical differences between older and more recent rocks, and explore the...
The High Resolution Stereo Camera (HRSC) of ESA's Mars Express is designed to map and investigate the topography of Mars. The camera, in particular its Super Resolution Channel (SRC), also obtains images of Phobos and Deimos on a regular basis. As HRSC is a push broom scanning instrument with nine CCD line detectors mounted in parallel, its unique...
At Gale crater, ChemCam acquired its first laser-induced breakdown spectroscopy (LIBS) target on Sol 13 of the landed portion of the mission. Up to Sol 800, more than 188,000 LIBS spectra were acquired on more than 5,800 points distributed over 650 individual targets. We present a comprehensive review of ChemCam scientific accomplishments during th...
Understanding of the geologic evolution of Mars has been greatly improved by recent orbital 1–3 , in situ 4,5 and meteorite 6–8 data, but insights into the earliest period of Martian magma-tism (4.1 to 3.7 billion years ago) remain scarce 9. The landing site of NASA's Curiosity rover, Gale crater, which formed 3.61 billion years ago 10 within older...
Understanding of the geologic evolution of Mars has been greatly improved by recent orbital, in situ and meteorite data, but insights into the earliest period of Martian magmatism (4.1 to 3.7 billion years ago) remain scarce. The landing site of NASA's Curiosity rover, Gale crater, which formed 3.61 billion years ago within older terrain, provides...
Impact processes at all scales have been involved in the formation and subsequent evolution of Gale crater. Small impact craters in the vicinity of the Curiosity MSL landing site and rover traverse during the 364 Sols after landing have been studied both from orbit and the surface. Evidence for the effect of impacts on basement outcrops may include...
Introduction: Fifty three igneous float rocks were identified along the Curiosity's traverse at Gale crater , between sol 13 and 800 [1, 2, 3]. Textural and compo-sitional analyses using MastCam, ChemCam Remote Micro Imager (RMI) and Laser Induced Breakdown Spectroscopy (LIBS) with a ∼300-500µm laser spot allow recognition of mafic and felsic igneo...
Here we present an adapted version of the Modified Gaussian Model (MGM), a tool developed to detect and characterize both simple and complex mineralogies in magmatic rocks, and we review the results we obtained over the last years on four different planetary bodies. We first describe the working principle of the adapted MGM technique, with the diff...
The Mars Science Laboratory rover, “Curiosity” landed near the base of a 5 km-high mound of layered material in Gale crater. Mounted on the rover mast, the ChemCam instrument is designed to remotely determine the composition of soils and rocks located a few meters from the rover, using a Laser-Induced Breakdown Spectrometer (LIBS) coupled to a Remo...
Ventifacts, rocks abraded by wind-borne particles, are found in Gale Crater, Mars. In the eastward drive from “Bradbury Landing” to “Rocknest,” they account for about half of the float and outcrop seen by Curiosity's cameras. Many are faceted and exhibit abrasion textures found at a range of scales, from sub-millimeter lineations to centimeter-scal...
One major reason for exploring Mars is the similarity of surface features to those present on Earth. Among the most important are morphological and mineralogical indicators that liquid water has existed on Mars at various locations over the entire history of the planet, albeit in decreasing abundance with time. Due to the strong evidence for aqueou...
Due to the strong evidence for aqueous processes at or near the surface, Mars is the most Earth-like body in the Solar System. After 10 years of ESA’s Mars Express orbiting the planet its High Resolution Stereo Camera (HRSC) covered about 90 % of the surface in stereo and color with resolutions up to 10 m/pixel [1]. Digital elevation models of up t...
The spatial variations of surface photometric parameters suggest different surface physical properties and thus a different history (formation and evolution).
The Curiosity rover discovered fine-grained sedimentary rocks, which are inferred to represent an ancient lake and preserve evidence of an environment that would have been suited to support a martian biosphere founded on chemolithoautotrophy. This aqueous environment was characterized by neutral pH, low salinity, and variable redox states of both i...
Textural and compositional analyses using Chemistry Camera (ChemCam) remote micro-imager and laser-induced breakdown spectroscopy (LIBS) have been performed on five float rocks and coarse gravels along the first 100 m of the Curiosity traverse at Bradbury Rise. ChemCam, the first LIBS instrument sent to another planet, offers the opportunity to ass...
This abstract describes the first imaging experiments performed at infinity focus with the ChemCam instrument onboard Curiosity.
Chemcam on Mars Science Laboratory analyzed mixtures of iron-rich and iron-poor phases in rocks. The mixtures average 56 ± 4 wt.% SiO2 and 36 ± 2 wt.% FeO.