NASA's Mars Research Articles

Active dust control and mitigation technology for lunar and Martian exploration

Mars is covered with a layer of dust that has been homogenized by global dust storms. Dust, levitated by these storms as well as by the frequent dust devils, is the dominant weather phenomenon on Mars. NASA's Mars exploration rovers have shown that atmospheric dust falling on solar panels can decrease their efficiency to the point of rendering the rover unusable. Dust covering the surface of the moon is expected to be electrostatically charged due to the solar wind, cosmic rays, and the solar radiation itself through the photoelectric effect. Electrostatically charged dust has a large tendency to adhere to surfaces. The Apollo missions to the moon showed that lunar dust adhesion can hinder manned and unmanned exploration activities. In this paper, we report on our efforts to develop an electrodynamic dust shield to prevent the accumulation of dust on surfaces and to remove dust already adhering to those surfaces. The technology uses electrostatic and dielectrophoretic forces to carry dust particles off surfaces and to generate an electrodynamic shield that prevents further accumulation of dust. The concept of the electrodynamic dust shield was introduced by NASA in the late 1960s and later reduced to practice during the 1970s for terrestrial applications. In 2003, our laboratory, in collaboration with several universities, applied this technology to space applications, specifically to remove dust from solar panels on Mars. We show how, with an appropriate design, we can prevent the electrostatic breakdown at the low Martian atmospheric pressures. We are also able to show that uncharged dust can be lifted and removed from surfaces under simulated Martian environmental conditions. We have also been able to develop a version of the electrodynamic dust shield working under hard vacuum conditions that simulate the lunar environment. We have implemented the electrodynamic dust shield on solar arrays, optical systems, spectrometers, viewports, thermal radiators, batteries, and power systems, as well as on fabrics for spacesuits. We present data on the design and optimization of the electrodynamic dust shields and provide data on the performance of the different implementations of the technology for lunar and Martian exploration activities.

The electrostatic environments of Mars and the Moon

The electrical activity present in the environment near the surfaces of Mars and the moon has very different origins and presents a challenge to manned and robotic planetary exploration missions. Mars is covered with a layer of dust that has been redistributed throughout the entire planet by global dust storms. Dust, levitated by these storms as well as by the frequent dust devils, is expected to be electrostatically charged due to the multiple grain collisions in the dust-laden atmosphere. Dust covering the surface of the moon is expected to be electrostatically charged due to the solar wind, cosmic rays, and the solar radiation itself through the photoelectric effect. Electrostatically charged dust has a large tendency to adhere to surfaces. NASA's Mars exploration rovers have shown that atmospheric dust falling on solar panels can decrease their efficiency to the point of rendering the rover unusable. And as the Apollo missions to the moon showed, lunar dust adhesion can hinder manned and unmanned lunar exploration activities. Taking advantage of the electrical activity on both planetary system bodies, dust removal technologies are now being developed that use electrostatic and dielectrophoretic forces to produce controlled dust motion. This paper presents a short review of the theoretical and semiempirical models that have been developed for the lunar and Martian electrical environments.

Q&A with project manager of NASA's next Mars rover

Q&A with project manager of NASA's next Mars rover

Thermal history of Mars inferred from orbital geochemistry of volcanic provinces

Reconstruction of the geological history of Mars has been the focus of considerable attention over the past four decades, with important discoveries being made about variations in surface conditions. However, despite a significant increase in the amount of data related to the morphology, mineralogy and chemistry of the martian surface, there is no clear global picture of how magmatism has evolved over time and how these changes relate to the internal workings and thermal evolution of the planet. Here we present geochemical data derived from the Gamma Ray Spectrometer on board NASA's Mars Odyssey spacecraft, focusing on twelve major volcanic provinces of variable age. Our analysis reveals clear trends in composition that are found to be consistent with varying degrees of melting of the martian mantle. There is evidence for thickening of the lithosphere (17-25 km Gyr(-1)) associated with a decrease in mantle potential temperature over time (30-40 K Gyr(-1)). Our inferred thermal history of Mars, unlike that of the Earth, is consistent with simple models of mantle convection.

Temporal observations of bright soil exposures at Gusev crater, Mars

This work is supported by grants and contracts from the NASA Mars Exploration Program (JPL) and the Mars Data Analysis Program (Cornell). M.S.R. was supported by a National Science Foundation Graduate Research Fellowship. E.A.C. and his lab facility are supported by grants from CSA, NSERC, CFI, MRIF, and the University of Winnipeg. J.J.W. thanks the NSF and the Fannie and John Hertz Foundation for support.

In Brief: Mineral sensors in orbit around Mars guide Opportunity rover

As NASA's Mars rover Opportunity travels around the red planet, researchers are using the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on board the Mars Reconnaissance Orbiter to guide the rover to interesting geology. This is the first time orbital mineral sensing has been used to determine where the rover should go, researchers said at the 2010 AGU Fall Meeting. The Opportunity rover is now near the edge of the 22‐kilometer‐wide Endeavor crater. CRISM has identified clay minerals in the region. The presence of clay minerals suggests that a less acidic, wet environment existed in the past. Some CRISM observations point to mineral clays that may be types that Opportunity has not investigated before.

Forecasting Spacecraft Telemetry Using Modified Physical Predictions

Abstract : Among systems that provide sensor data of their performance, one approach to prognostic estimation is forecasting, i.e. prediction of measurable parameters and comparison of predicted values against established operational limits. Forecasting can be attempted statistically, or can be based on rigorous physical simulation. However, combining these approaches is difficult where system mode behavior or timing of system activities is uncertain, limiting the accuracy or applicability of a forecast. In this paper we describe a method to modify simulation outputs to better match current telemetry. We begin with a familiar autoregressive approach to model residuals between predicted spacecraft performance, provided by physics-based modeling tools, and up-to-date spacecraft telemetry. This result is then improved by transforming the simulation result to better fit recent data, and the transformation is applied to generate more accurate future predictions. The method is suitable for real-time signal prediction. We will motivate this approach and characterize its performance using example telemetry from the NASA Mars Exploration Rover spacecraft.*

The miniaturized Möessbauer spectrometer MIMOS II for the Phobos-Grunt mission

Moessbauer spectroscopy is a powerful tool for the mineralogical analysis of Fe-bearing materials. The miniaturized Moessbauer spectrometer MIMOS II has already been working on the surface of Mars for 6 years as part of the NASA Mars Exploration Rovers mission. The improved version of the instrument is a component of the scientific payload of the Phobos-Grunt mission. The scientific objectives of the instrument are the following: to identify the iron-bearing phases, to determine the quantitative distribution of iron among these phases, and to determine the distribution of iron among its oxidation states.

The Mawrth Vallis Region of Mars: A Potential Landing Site for the Mars Science Laboratory (MSL) Mission

The primary objective of NASA's Mars Science Laboratory (MSL) mission, which will launch in 2011, is to characterize the habitability of a site on Mars through detailed analyses of the composition and geological context of surface materials. Within the framework of established mission goals, we have evaluated the value of a possible landing site in the Mawrth Vallis region of Mars that is targeted directly on some of the most geologically and astrobiologically enticing materials in the Solar System. The area around Mawrth Vallis contains a vast (>1 × 10⁶ km²) deposit of phyllosilicate-rich, ancient, layered rocks. A thick (>150 m) stratigraphic section that exhibits spectral evidence for nontronite, montmorillonite, amorphous silica, kaolinite, saponite, other smectite clay minerals, ferrous mica, and sulfate minerals indicates a rich geological history that may have included multiple aqueous environments. Because phyllosilicates are strong indicators of ancient aqueous activity, and the preservation potential of biosignatures within sedimentary clay deposits is high, martian phyllosilicate deposits are desirable astrobiological targets. The proposed MSL landing site at Mawrth Vallis is located directly on the largest and most phyllosilicate-rich deposit on Mars and is therefore an excellent place to explore for evidence of life or habitability.

Spacecraft aerodynamics and trajectory simulation during aerobraking

This paper uses a direct simulation Monte Carlo (DSMC) approach to simulate rarefied aerodynamic characteristics during the aerobraking process of the NASA Mars Global Surveyor (MGS) spacecraft. The research focuses on the flowfield and aerodynamic characteristics distribution under various free stream densities. The variation regularity of aerodynamic coefficients is analyzed. The paper also develops an aerodynamics-aeroheating-trajectory integrative simulation model to preliminarily calculate the aerobraking orbit transfer by combining the DSMC technique and the classical kinematics theory. The results show that the effect of the planetary atmospheric density, the spacecraft yaw, and the pitch attitudes on the spacecraft aerodynamics is significant. The numerical results are in good agreement with the existing results reported in the literature. The aerodynamics-aeroheating-trajectory integrative simulation model can simulate the orbit transfer in the complete aerobraking mission. The current results of the spacecraft trajectory show that the aerobraking maneuvers have good performance of attitude control.

Simulations of atmospheric phenomena at the Phoenix landing site with the Ames General Circulation Model

Phoenix, the first NASA Mars Scout class mission, was designed to “follow the water” and study the polar region. Landing in late northern spring, Phoenix measured soil chemistry, near‐surface water ice, and studied numerous atmospheric properties and weather phenomena. Here, we use atmospheric measurements made by Phoenix to test and calibrate the Ames General Circulation Model (GCM) and start the process of analyzing and interpreting the vast data set provided by this groundbreaking mission. The GCM reproduces surface pressures and temperatures within the measured diurnal and seasonal ranges. It also reproduces measured water ice cloud profiles with ground fogs forming after Ls = 120° and a separate cloud deck between 3 km and 6 km above the surface. Near‐surface water vapor pressures have daytime maxima above 1 Pa in both the data and model. We find that frosts and fogs observed by Phoenix are correlated with the formation of high‐pressure weather systems over the landing site.

Calibrating the ChemCam laser-induced breakdown spectroscopy instrument for carbonate minerals on Mars

The ChemCam instrument suite onboard the NASA Mars Science Laboratory rover includes the first laser-induced breakdown spectroscopy (LIBS) instrument for extraterrestrial applications. Here we examine carbonate minerals in a simulated martian environment to better understand the LIBS signature of these materials on Mars. Both chemical composition and rock type are determined using multivariate analysis techniques. Composition is confirmed using scanning electron microscopy. Our results show that ChemCam can recognize and differentiate between different types of carbonate materials on Mars.

Mars Rover Enters New Phase of Mission

The wandering days for NASA's Mars Exploration Rover Spirit appear to be over. Spirit, which has been exploring the planet on a science mission since January 2004, is embedded in sandy soil and will remain at its current location at 14.6°S, 175.5°E, at the “Home Plate” plateau within Gusev crater, through the coming Martian winter and for the rest of its days.Despite NASA's best efforts to extricate the six‐wheeled Spirit from the sulfate salt—rich soil for the past 8 months, mission scientists indicated on 26 January that they now believe the rover is stuck for good, aside from minor movements on its four remaining operational wheels and other small adjustments. For the next several weeks, NASA will continue efforts to slightly reposition the robot so that it can better catch the Sun, endure the coming Martian winter in a state of hibernation, and remain at least in infrequent communication with the science team.

Multi-resolution topographic data extraction from Martian stereo imagery

The acquisition of high resolution topographic data such as Digital Terrain Models (DTMs) and orthoimages from various Martian stereo imagery is now readily available. The very successful European Space Agency (ESA) Mars Express mission includes the High Resolution Stereo Camera (HRSC) which has provided, since March 2004, an increasingly global set of along-track stereo coverage at relatively high spatial resolution (<100 m, mainly 12.5–25 m) over the Martian surface. Previous DTM generation was only accomplished with planned or serendipitous Viking Orbiter and more recently from Mars Orbiter Camera Narrow Angle (MOC-NA) stereo-pairs. Neither system was designed for stereo photogrammetric DTM generation. Recently, the NASA Mars Reconnaissance Orbiter (MRO) deployed two major optical pushbroom CCD cameras which are capable of across-track stereo targeting. Both Context Camera (CTX) and High Resolution Imaging Science Experiment (HiRISE) provide very high resolution stereo imagery at 6 m and submetre, respectively. A stereo processing chain has been developed which uses a non-rigorous sensor model with geodetic control derived from a reference stereo data source (HRSC) and is here shown to be successfully applied to CTX and HiRISE stereo imagery for 3 test areas. This processing chain is here demonstrated to generate excellent quality DTMs (up to a maximum grid spacing of 0.7 m with HiRISE and 10 m with CTX) and associated ortho images. The photogrammetric quality of these products is here verified using inter-comparisons with HRSC and Mars Orbiter Laser Altimeter (MOLA) data sets and shows good agreement.

Design and fabrication of lenses for the color science cameras aboard the Mars Science Laboratory rover

The NASA Mars Science Laboratory (MSL) rover is the third-generation robotic vehicle planned for Mars exploration, scheduled to land on Mars in 2012. There are 15 cameras on board the rover, 10 of which have engineering functions and 5 of which are designed for scientific investigations. Four of the five science cameras are built by Malin Space Science Systems to acquire color images via an RGB Bayer pattern 1600×1200 pixel charge-coupled device. These cameras are categorized into three types: Mast Camera (Mastcam), of which two different versions will be flown; Mars Hand Lens Imager (MAHLI); and Mars Descent Imager (MARDI). These cameras will investigate Martian geology and geomorphology and provide the first color views of the Martian surface that are identical to the natural color provided by typical consumer digital cameras. The author designed and built the lenses for these MSL science cameras, Mastcam utilizes a 34-mm focal length F/8 and a 100-mm focal length F/10 lens; MAHLI utilizes a lens that varies from a 18.4-mm focal length F/9.8 (close focus) to 21.4-mm focal length F/8.5 (infinity focus); and MARDI utilizes a 9.7-mm focal length F/3 lens. The requirements, design, and performance of these lenses are described.

Transient teleconnection event at the onset of a planet-encircling dust storm on Mars

Abstract. We use proper orthogonal decomposition (POD) to study a transient teleconnection event at the onset of the 2001 planet-encircling dust storm on Mars, in terms of empirical orthogonal functions (EOFs). There are several differences between this and previous studies of atmospheric events using EOFs. First, instead of using a single variable such as surface pressure or geopotential height on a given pressure surface, we use a dataset describing the evolution in time of global and fully three-dimensional atmospheric fields such as horizontal velocity and temperature. These fields are produced by assimilating Thermal Emission Spectrometer observations from NASA's Mars Global Surveyor spacecraft into a Mars general circulation model. We use total atmospheric energy (TE) as a physically meaningful quantity which weights the state variables. Second, instead of adopting the EOFs to define teleconnection patterns as planetary-scale correlations that explain a large portion of long time-scale variability, we use EOFs to understand transient processes due to localised heating perturbations that have implications for the atmospheric circulation over distant regions. The localised perturbation is given by anomalous heating due to the enhanced presence of dust around the northern edge of the Hellas Planitia basin on Mars. We show that the localised disturbance is seemingly restricted to a small number (a few tens) of EOFs. These can be classified as low-order, transitional, or high-order EOFs according to the TE amount they explain throughout the event. Despite the global character of the EOFs, they show the capability of accounting for the localised effects of the perturbation via the presence of specific centres of action. We finally discuss possible applications for the study of terrestrial phenomena with similar characteristics.

NASA's Mars rover is really stuck

NASA's Mars rover is really stuck

Neutron components of radiation environment in the near-Earth and near-Mars space

Comparison is presented for neutron components of radiation environment in the near-Earth and near-Mars space, which is based on data from high energy neutron detector (HEND) instrument onboard NASA Mars Odyssey and data from BTN-M1 instrument onboard Russian segment of International Space Station.

Mars Reconnaissance Orbiter Mars Color Imager (MARCI): Instrument description, calibration, and performance

The Mars Color Imager (MARCI) instrument aboard the NASA Mars Reconnaissance Orbiter spacecraft is a wide‐angle, multispectral Charge‐Coupled Device (CCD) “push frame” imaging camera designed to provide frequent, synoptic‐scale color imaging of the Martian atmosphere and surface. MARCI uses a 1024 × 1024 pixel interline transfer CCD detector that has seven narrowband interference filters bonded directly to the CCD. Five of the filters are in the visible to short‐wave near‐infrared wavelength range (437, 546, 604, 653, and 718 nm) and two are in the ultraviolet range (258 and 320 nm). Here we describe the scientific objectives of the MARCI investigation and the basic characteristics, calibration, and in‐flight performance of the MARCI instrument. We include several examples of early scientific results and investigations enabled by an extensive preflight and in‐flight calibration program and by validation of the performance of the instrument in flight.

Mars rover needs a date

NASA's Mars Science Laboratory needs more money to reach the launch pad, and has less time.