1
|
Abstract
Data analysis methods have scarcely kept pace with the rapid increase in Earth observations, spurring the development of novel algorithms, storage methods, and computational techniques. For scientists interested in Mars, the problem is always the same: there is simultaneously never enough of the right data and an overwhelming amount of data in total. Finding sufficient data needles in a haystack to test a hypothesis requires hours of manual data screening, and more needles and hay are added constantly. To date, the vast majority of Martian research has been focused on either one-off local/regional studies or on hugely time-consuming manual global studies. Machine learning in its numerous forms can be helpful for future such work. Machine learning has the potential to help map and classify a large variety of both features and properties on the surface of Mars and to aid in the planning and execution of future missions. Here, we outline the current extent of machine learning as applied to Mars, summarize why machine learning should be an important tool for planetary geomorphology in particular, and suggest numerous research avenues and funding priorities for future efforts. We conclude that: (1) moving toward methods that require less human input (i.e., self- or semi-supervised) is an important paradigm shift for Martian applications, (2) new robust methods using generative adversarial networks to generate synthetic high-resolution digital terrain models represent an exciting new avenue for Martian geomorphologists, (3) more effort and money must be directed toward developing standardized datasets and benchmark tests, and (4) the community needs a large-scale, generalized, and programmatically accessible geographic information system (GIS).
Collapse
|
2
|
Aeolian abrasion of rocks as a mechanism to produce methane in the Martian atmosphere. Sci Rep 2019; 9:8229. [PMID: 31160623 PMCID: PMC6546745 DOI: 10.1038/s41598-019-44616-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 05/16/2019] [Indexed: 11/08/2022] Open
Abstract
Seasonal changes in methane background levels and methane spikes have been detected in situ a metre above the Martian surface, and larger methane plumes detected via ground-based remote sensing, however their origin have not yet been adequately explained. Proposed methane sources include the UV irradiation of meteoritic-derived organic matter, hydrothermal reactions with olivine, organic breakdown via meteoroid impact, release from gas hydrates, biological production, or the release of methane from fluid inclusions in basalt during aeolian erosion. Here we quantify for the first time the potential importance of aeolian abrasion as a mechanism for releasing trapped methane from within rocks, by coupling estimates of present day surface wind abrasion with the methane contents of a variety of Martian meteorites, analogue terrestrial basalts and analogue terrestrial sedimentary rocks. We demonstrate that the abrasion of basalt under present day Martian rates of aeolian erosion is highly unlikely to produce detectable changes in methane concentrations in the atmosphere. We further show that, although there is a greater potential for methane production from the aeolian abrasion of certain sedimentary rocks, to produce the magnitude of methane concentrations analysed by the Curiosity rover they would have to contain methane in similar concentrations as economic reserved of biogenic/thermogenic deposits on Earth. Therefore we suggest that aeolian abrasion is an unlikely origin of the methane detected in the Martian atmosphere, and that other methane sources are required.
Collapse
|
3
|
Klimczak C, Kling CL, Byrne PK. Topographic Expressions of Large Thrust Faults on Mars. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2018; 1123:1973-1995. [PMID: 30237952 PMCID: PMC6142183 DOI: 10.1029/2017je005448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 07/01/2018] [Indexed: 06/08/2023]
Abstract
On planets with little erosion, thrust faults produce broad, asymmetric, positive-relief, linear to arcuate ridges -often referred to as lobate scarps- that remain largely unaltered, such that their topographic expressions are a measure of the structural uplift caused by the displacement and associated country-rock deformation of the faults. Here we map and systematically assess the structural relief of 24 thrust faults across Mars to infer their growth behavior. Our mapping indicates that the majority of individual thrust faults have simple, linear map traces with lengths of up to ~450 km, but that some thrust faults form systems of up to 1400 km in length. For the most topographically pronounced landforms, the structural relief developed above the fault is as great as ~3400 m. We then relate topographic measurements to the displacement on the underlying fault planes to study the displacement variations along the fault length. We find a variety of displacement distribution shapes of the fault systems, which we attribute to differences in fault growth that include unrestricted and restricted growth, linkage, and/or fault interaction. Finally, we relate the maximum displacements (Dmax ) determined for each of the faults to their respective fault length (L) to establish a maximum displacement-to-length relationship. The observed scaling characteristics and order-of-magnitude scatter of our Dmax/L data are not uncommon for fault populations on Earth and tie in well with the map patterns, tectonic geomorphology, and systematic along-strike displacement distributions to have grown in a basement-block faulting style found in intra-plate tectonic settings on Earth.
Collapse
Affiliation(s)
- Christian Klimczak
- Structural Geology and Geomechanics Group, Department of Geology, University of Georgia, Athens, GA 30602
| | - Corbin L. Kling
- Structural Geology and Geomechanics Group, Department of Geology, University of Georgia, Athens, GA 30602
- Planetary Research Group, Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695
| | - Paul K. Byrne
- Planetary Research Group, Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695
| |
Collapse
|
4
|
Rogers AD, Warner NH, Golombek MP, Head JW, Cowart JC. Areally Extensive Surface Bedrock Exposures on Mars: Many Are Clastic Rocks, Not Lavas. GEOPHYSICAL RESEARCH LETTERS 2018; 45:1767-1777. [PMID: 30598561 PMCID: PMC6310033 DOI: 10.1002/2018gl077030] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Areally extensive exposures of intact olivine/pyroxene-enriched rock, as well as feldspar-enriched rock, are found in isolated locations throughout the Martian highlands. The petrogenetic origin(s) of these rock units are not well understood, but some previous studies favored an effusive volcanic origin partly on the basis of distinctive composition and relatively high thermal inertia. Here we show that the regolith development, crater retention, and morphological characteristics for many of these "bedrock plains" are not consistent with competent lavas and reinterpret the high thermal inertia orbital signatures to represent friable materials that are more easily kept free of comminution products through eolian activity. Candidate origins include pyroclastic rocks, impact-generated materials, or detrital sedimentary rocks. Olivine/pyroxene enrichments in bedrock plains relative to surrounding materials could have potentially formed through deflation and preferential removal of plagioclase.
Collapse
Affiliation(s)
- A Deanne Rogers
- Department of Geosciences, Stony Brook University, Stony Brook, NY, USA
| | - Nicholas H Warner
- Department of Geological Sciences, State University of New York at Geneseo, Geneseo, NY, USA
| | - Matthew P Golombek
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - James W Head
- Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, USA
| | - Justin C Cowart
- Department of Geosciences, Stony Brook University, Stony Brook, NY, USA
| |
Collapse
|
5
|
Amazonian chemical weathering rate derived from stony meteorite finds at Meridiani Planum on Mars. Nat Commun 2016; 7:13459. [PMID: 27834377 PMCID: PMC5114618 DOI: 10.1038/ncomms13459] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 09/26/2016] [Indexed: 11/08/2022] Open
Abstract
Spacecraft exploring Mars such as the Mars Exploration Rovers Spirit and Opportunity, as well as the Mars Science Laboratory or Curiosity rover, have accumulated evidence for wet and habitable conditions on early Mars more than 3 billion years ago. Current conditions, by contrast, are cold, extremely arid and seemingly inhospitable. To evaluate exactly how dry today's environment is, it is important to understand the ongoing current weathering processes. Here we present chemical weathering rates determined for Mars. We use the oxidation of iron in stony meteorites investigated by the Mars Exploration Rover Opportunity at Meridiani Planum. Their maximum exposure age is constrained by the formation of Victoria crater and their minimum age by erosion of the meteorites. The chemical weathering rates thus derived are ∼1 to 4 orders of magnitude slower than that of similar meteorites found in Antarctica where the slowest rates are observed on Earth. Little is known about the impacts of Mars' contemporary dryness on weathering processes. Here, using iron oxidation estimates from the Mars Rover Opportunity, the authors quantify chemical weathering rates for Mars, finding appreciably slower rates compared with the lowest values on Earth.
Collapse
|
6
|
Tirsch D, Jaumann R, Pacifici A, Poulet F. Dark aeolian sediments in Martian craters: Composition and sources. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2009je003562] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
7
|
Grotzinger J, Beaty D, Dromart G, Gupta S, Harris M, Hurowitz J, Kocurek G, McLennan S, Milliken R, Ori GG, Sumner D. Mars sedimentary geology: key concepts and outstanding questions. ASTROBIOLOGY 2011; 11:77-87. [PMID: 21294660 DOI: 10.1089/ast.2010.0571] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Affiliation(s)
- John Grotzinger
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91106, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Golombek M, Robinson K, McEwen A, Bridges N, Ivanov B, Tornabene L, Sullivan R. Constraints on ripple migration at Meridiani Planum from Opportunity and HiRISE observations of fresh craters. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010je003628] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
9
|
Warner N, Gupta S, Lin SY, Kim JR, Muller JP, Morley J. Late Noachian to Hesperian climate change on Mars: Evidence of episodic warming from transient crater lakes near Ares Vallis. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009je003522] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
10
|
Halevy I, Pierrehumbert RT, Schrag DP. Radiative transfer in CO2-rich paleoatmospheres. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2009jd011915] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
11
|
Segura TL, Toon OB, Colaprete A. Modeling the environmental effects of moderate-sized impacts on Mars. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008je003147] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
12
|
Zacny K, Bar-Cohen Y, Brennan M, Briggs G, Cooper G, Davis K, Dolgin B, Glaser D, Glass B, Gorevan S, Guerrero J, McKay C, Paulsen G, Stanley S, Stoker C. Drilling systems for extraterrestrial subsurface exploration. ASTROBIOLOGY 2008; 8:665-706. [PMID: 18598141 DOI: 10.1089/ast.2007.0179] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Drilling consists of 2 processes: breaking the formation with a bit and removing the drilled cuttings. In rotary drilling, rotational speed and weight on bit are used to control drilling, and the optimization of these parameters can markedly improve drilling performance. Although fluids are used for cuttings removal in terrestrial drilling, most planetary drilling systems conduct dry drilling with an auger. Chip removal via water-ice sublimation (when excavating water-ice-bound formations at pressure below the triple point of water) and pneumatic systems are also possible. Pneumatic systems use the gas or vaporization products of a high-density liquid brought from Earth, gas provided by an in situ compressor, or combustion products of a monopropellant. Drill bits can be divided into coring bits, which excavate an annular shaped hole, and full-faced bits. While cylindrical cores are generally superior as scientific samples, and coring drills have better performance characteristics, full-faced bits are simpler systems because the handling of a core requires a very complex robotic mechanism. The greatest constraints to extraterrestrial drilling are (1) the extreme environmental conditions, such as temperature, dust, and pressure; (2) the light-time communications delay, which necessitates highly autonomous systems; and (3) the mission and science constraints, such as mass and power budgets and the types of drilled samples needed for scientific analysis. A classification scheme based on drilling depth is proposed. Each of the 4 depth categories (surface drills, 1-meter class drills, 10-meter class drills, and deep drills) has distinct technological profiles and scientific ramifications.
Collapse
Affiliation(s)
- K Zacny
- Honeybee Robotics Spacecraft Mechanisms Corporation, New York, NY 10001, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Yingst RA, Haldemann AFC, Biedermann KL, Monhead AM. Quantitative morphology of rocks at the Mars Pathfinder landing site. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2005je002582] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
14
|
Preblich BS, McEwen AS, Studer DM. Mapping rays and secondary craters from the Martian crater Zunil. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006je002817] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
15
|
McEwen AS, Eliason EM, Bergstrom JW, Bridges NT, Hansen CJ, Delamere WA, Grant JA, Gulick VC, Herkenhoff KE, Keszthelyi L, Kirk RL, Mellon MT, Squyres SW, Thomas N, Weitz CM. Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment (HiRISE). ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2005je002605] [Citation(s) in RCA: 1056] [Impact Index Per Article: 62.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
16
|
Golombek MP, Grant JA, Crumpler LS, Greeley R, Arvidson RE, Bell JF, Weitz CM, Sullivan R, Christensen PR, Soderblom LA, Squyres SW. Erosion rates at the Mars Exploration Rover landing sites and long-term climate change on Mars. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2006je002754] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- M. P. Golombek
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - J. A. Grant
- Center for Earth and Planetary Studies, National Air and Space Museum; Smithsonian Institution; Washington, DC USA
| | - L. S. Crumpler
- New Mexico Museum of Natural History and Science; Albuquerque New Mexico USA
| | - R. Greeley
- Department of Geological Sciences; Arizona State University; Tempe Arizona USA
| | - R. E. Arvidson
- Department of Earth and Planetary Sciences; Washington University; St. Louis Missouri USA
| | - J. F. Bell
- Department of Astronomy; Cornell University; Ithaca New York USA
| | - C. M. Weitz
- Planetary Science Institute; Tucson Arizona USA
| | - R. Sullivan
- Department of Astronomy; Cornell University; Ithaca New York USA
| | - P. R. Christensen
- Department of Geological Sciences; Arizona State University; Tempe Arizona USA
| | | | - S. W. Squyres
- Department of Astronomy; Cornell University; Ithaca New York USA
| |
Collapse
|
17
|
Golombek MP, Crumpler LS, Grant JA, Greeley R, Cabrol NA, Parker TJ, Rice JW, Ward JG, Arvidson RE, Moersch JE, Fergason RL, Christensen PR, Castaño A, Castaño R, Haldemann AFC, Li R, Bell JF, Squyres SW. Geology of the Gusev cratered plains from the Spirit rover transverse. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005je002503] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- M. P. Golombek
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - L. S. Crumpler
- New Mexico Museum of Natural History and Science; Albuquerque New Mexico USA
| | | | - R. Greeley
- Department of Geological Sciences; Arizona State University; Tempe Arizona USA
| | - N. A. Cabrol
- NASA Ames Research Center; Moffett Field California USA
| | - T. J. Parker
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - J. W. Rice
- Department of Geological Sciences; Arizona State University; Tempe Arizona USA
| | - J. G. Ward
- Department of Earth and Planetary Sciences; Washington University; St. Louis Missouri USA
| | - R. E. Arvidson
- Department of Earth and Planetary Sciences; Washington University; St. Louis Missouri USA
| | - J. E. Moersch
- Department of Geological Sciences; University of Tennessee; Knoxville Tennessee USA
| | - R. L. Fergason
- Department of Geological Sciences; Arizona State University; Tempe Arizona USA
| | - P. R. Christensen
- Department of Geological Sciences; Arizona State University; Tempe Arizona USA
| | - A. Castaño
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - R. Castaño
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - A. F. C. Haldemann
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - R. Li
- Department of Civil and Environmental Engineering and Geodetic Science; Ohio State University; Columbus Ohio USA
| | - J. F. Bell
- Department of Astronomy; Cornell University; Ithaca New York USA
| | - S. W. Squyres
- Department of Astronomy; Cornell University; Ithaca New York USA
| |
Collapse
|
18
|
Solomon SC, Aharonson O, Aurnou JM, Banerdt WB, Carr MH, Dombard AJ, Frey HV, Golombek MP, Hauck SA, Head JW, Jakosky BM, Johnson CL, McGovern PJ, Neumann GA, Phillips RJ, Smith DE, Zuber MT. New Perspectives on Ancient Mars. Science 2005; 307:1214-20. [PMID: 15731435 DOI: 10.1126/science.1101812] [Citation(s) in RCA: 225] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Mars was most active during its first billion years. The core, mantle, and crust formed within approximately 50 million years of solar system formation. A magnetic dynamo in a convecting fluid core magnetized the crust, and the global field shielded a more massive early atmosphere against solar wind stripping. The Tharsis province became a focus for volcanism, deformation, and outgassing of water and carbon dioxide in quantities possibly sufficient to induce episodes of climate warming. Surficial and near-surface water contributed to regionally extensive erosion, sediment transport, and chemical alteration. Deep hydrothermal circulation accelerated crustal cooling, preserved variations in crustal thickness, and modified patterns of crustal magnetization.
Collapse
Affiliation(s)
- Sean C Solomon
- Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Bridges NT, Phoreman J, White BR, Greeley R, Eddlemon EE, Wilson GR, Meyer CJ. Trajectories and energy transfer of saltating particles onto rock surfaces: Application to abrasion and ventifact formation on Earth and Mars. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2004je002388] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
20
|
Howard AD, Moore JM, Irwin RP. An intense terminal epoch of widespread fluvial activity on early Mars: 1. Valley network incision and associated deposits. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2005je002459] [Citation(s) in RCA: 248] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
21
|
Heldmann JL. Formation of Martian gullies by the action of liquid water flowing under current Martian environmental conditions. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2004je002261] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
22
|
Irwin RP, Howard AD, Craddock RA, Moore JM. An intense terminal epoch of widespread fluvial activity on early Mars: 2. Increased runoff and paleolake development. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2005je002460] [Citation(s) in RCA: 298] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
23
|
Greeley R, Squyres SW, Arvidson RE, Bartlett P, Bell JF, Blaney D, Cabrol NA, Farmer J, Farrand B, Golombek MP, Gorevan SP, Grant JA, Haldemann AFC, Herkenhoff KE, Johnson J, Landis G, Madsen MB, McLennan SM, Moersch J, Rice JW, Richter L, Ruff S, Sullivan RJ, Thompson SD, Wang A, Weitz CM, Whelley P. Wind-related processes detected by the Spirit Rover at Gusev Crater, Mars. Science 2004; 305:810-3. [PMID: 15297660 DOI: 10.1126/science.1100108] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Wind-abraded rocks, ripples, drifts, and other deposits of windblown sediments are seen at the Columbia Memorial Station where the Spirit rover landed. Orientations of these features suggest formative winds from the north-northwest, consistent with predictions from atmospheric models of afternoon winds in Gusev Crater. Cuttings from the rover Rock Abrasion Tool are asymmetrically distributed toward the south-southeast, suggesting active winds from the north-northwest at the time (midday) of the abrasion operations. Characteristics of some rocks, such as a two-toned appearance, suggest that they were possibly buried and exhumed on the order of 5 to 60 centimeters by wind deflation, depending on location.
Collapse
Affiliation(s)
- R Greeley
- Department of Geological Sciences, Arizona State University, Box 871404, Tempe, AZ 85287-1404, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Grant JA, Arvidson R, Bell JF, Cabrol NA, Carr MH, Christensen P, Crumpler L, Des Marais DJ, Ehlmann BL, Farmer J, Golombek M, Grant FD, Greeley R, Herkenhoff K, Li R, McSween HY, Ming DW, Moersch J, Rice JW, Ruff S, Richter L, Squyres S, Sullivan R, Weitz C. Surficial Deposits at Gusev Crater Along Spirit Rover Traverses. Science 2004; 305:807-10. [PMID: 15297659 DOI: 10.1126/science.1099849] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The Mars Exploration Rover Spirit has traversed a fairly flat, rock-strewn terrain whose surface is shaped primarily by impact events, although some of the landscape has been altered by eolian processes. Impacts ejected basaltic rocks that probably were part of locally formed lava flows from at least 10 meters depth. Some rocks have been textured and/or partially buried by windblown sediments less than 2 millimeters in diameter that concentrate within shallow, partially filled, circular impact depressions referred to as hollows. The terrain traversed during the 90-sol (martian solar day) nominal mission shows no evidence for an ancient lake in Gusev crater.
Collapse
Affiliation(s)
- J A Grant
- Center for Earth and Planetary Studies, National Air and Space Museum, Smithsonian Institution, Washington, DC 20560, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Forsberg-Taylor NK. Crater degradation in the Martian highlands: Morphometric analysis of the Sinus Sabaeus region and simulation modeling suggest fluvial processes. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2004je002242] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
26
|
|
27
|
Arvidson RE, Anderson RC, Haldemann AFC, Landis GA, Li R, Lindemann RA, Matijevic JR, Morris RV, Richter L, Squyres SW, Sullivan RJ, Snider NO. Physical properties and localization investigations associated with the 2003 Mars Exploration rovers. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002je002041] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- R. E. Arvidson
- McDonnell Center for the Space Sciences, Department of Earth and Planetary Sciences; Washington University; St. Louis Missouri USA
| | | | | | | | - R. Li
- Department of Civil and Environmental Engineering and Geodetic Science; Ohio State University; Columbus Ohio USA
| | | | | | | | - L. Richter
- DLR Institut für Raumsimulation; Köln Germany
| | - S. W. Squyres
- Center for Radiophysics and Space Research; Cornell University; Ithaca New York USA
| | - R. J. Sullivan
- Center for Radiophysics and Space Research; Cornell University; Ithaca New York USA
| | - N. O. Snider
- McDonnell Center for the Space Sciences, Department of Earth and Planetary Sciences; Washington University; St. Louis Missouri USA
| |
Collapse
|
28
|
Golombek MP, Haldemann AFC, Forsberg-Taylor NK, DiMaggio EN, Schroeder RD, Jakosky BM, Mellon MT, Matijevic JR. Rock size-frequency distributions on Mars and implications for Mars Exploration Rover landing safety and operations. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002je002035] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- M. P. Golombek
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - A. F. C. Haldemann
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - N. K. Forsberg-Taylor
- Department of Environmental Sciences; University of Virginia; Charlottesville Virginia USA
| | - E. N. DiMaggio
- Department of Geological Sciences; University of Michigan; Ann Arbor Michigan USA
| | - R. D. Schroeder
- Department of Geology; California State University; Bakersfield California USA
| | - B. M. Jakosky
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - M. T. Mellon
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - J. R. Matijevic
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| |
Collapse
|
29
|
Kminek G, Bada JL, Pogliano K, Ward JF. Radiation-dependent limit for the viability of bacterial spores in halite fluid inclusions and on Mars. Radiat Res 2003; 159:722-9. [PMID: 12751954 PMCID: PMC3919141 DOI: 10.1667/0033-7587(2003)159[0722:rlftvo]2.0.co;2] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
When claims for the long-term survival of viable organisms are made, either within terrestrial minerals or on Mars, considerations should be made of the limitations imposed by the naturally occurring radiation dose to which they have been exposed. We investigated the effect of ionizing radiation on different bacterial spores by measuring the inactivation constants for B. subtilis and S. marismortui spores in solution as well as for dry spores of B. subtilis and B. thuringiensis. S. marismortui is a halophilic spore that is genetically similar to the recently discovered 2-9-3 bacterium from a halite fluid inclusion, claimed to be 250 million years old (Vreeland et al., Nature 407, 897-900, 2000). B. thuringiensis is a soil bacterium that is genetically similar to the human pathogens B. anthracis and B. cereus (Helgason et al., Appl. Environ. Microbiol. 66, 2627-2630, 2000). To relate the inactivation constant to some realistic environments, we calculated the radiation regimen in a halite fluid inclusion and in the Martian subsurface over time. Our conclusion is that the ionizing dose of radiation in those environments limits the survival of viable bacterial spores over long periods. In the absence of an active repair mechanism in the dormant state, the long-term survival of spores is limited to less than 109 million years in halite fluid inclusions, to 100 to 160 million years in the Martian subsurface below 3 m, and to less than 600,000 years in the uppermost meter of Mars.
Collapse
Affiliation(s)
- Gerhard Kminek
- Scripps Institution of Oceanography, University of California, San Diego, USA.
| | | | | | | |
Collapse
|
30
|
|
31
|
Carr MH. Oceans on Mars: An assessment of the observational evidence and possible fate. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002je001963] [Citation(s) in RCA: 234] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
32
|
Treiman AH. Geologic settings of Martian gullies: Implications for their origins. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002je001900] [Citation(s) in RCA: 164] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
33
|
Carr MH. Elevations of water-worn features on Mars: Implications for circulation of groundwater. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2002je001845] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
34
|
Abstract
The martian valley networks formed near the end of the period of heavy bombardment of the inner solar system, about 3.5 billion years ago. The largest impacts produced global blankets of very hot ejecta, ranging in thickness from meters to hundreds of meters. Our simulations indicated that the ejecta warmed the surface, keeping it above the freezing point of water for periods ranging from decades to millennia, depending on impactor size, and caused shallow subsurface or polar ice to evaporate or melt. Large impacts also injected steam into the atmosphere from the craters or from water innate to the impactors. From all sources, a typical 100-, 200-, or 250-kilometers asteroid injected about 2, 9, or 16 meters, respectively, of precipitable water into the atmosphere, which eventually rained out at a rate of about 2 meters per year. The rains from a large impact formed rivers and contributed to recharging aquifers.
Collapse
Affiliation(s)
- Teresa L Segura
- Program in Atmospheric and Oceanic Sciences, Laboratory for Atmospheric and Space Physics, University of Colorado, Campus Box 392, Boulder, CO 80309-0392, USA
| | | | | | | |
Collapse
|
35
|
Affiliation(s)
- Robert A. Craddock
- Center for Earth and Planetary Studies, National Air and Space Museum; Smithsonian Institution; Washington District of Columbia USA
| | - Alan D. Howard
- Department of Environmental Sciences; University of Virginia; Charlottesville Virginia USA
| |
Collapse
|
36
|
Milkovich SM. Meltback of Hesperian-aged ice-rich deposits near the south pole of Mars: Evidence for drainage channels and lakes. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001je001802] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
37
|
Greeley R. Terrestrial analogs to wind-related features at the Viking and Pathfinder landing sites on Mars. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2000je001481] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
38
|
Williams RME, Phillips RJ. Morphometric measurements of martian valley networks from Mars Orbiter Laser Altimeter (MOLA) data. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001409] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
39
|
Abstract
Over the past 30 years, the water-generated landforms and landscapes of Mars have been revealed in increasing detail by a succession of spacecraft missions. Recent data from the Mars Global Surveyor mission confirm the view that brief episodes of water-related activity, including glaciation, punctuated the geological history of Mars. The most recent of these episodes seems to have occurred within the past 10 million years. These new results are anomalous in regard to the prevailing view that the martian surface has been continuously extremely cold and dry, much as it is today, for the past 3.9 billion years. Interpretations of the new data are controversial, but explaining the anomalies in a consistent manner leads to potentially fruitful hypotheses for understanding the evolution of Mars in relation to Earth.
Collapse
Affiliation(s)
- V R Baker
- Department of Hydrology and Water Resources, University of Arizona, Tucson, Arizona 85721-0011, USA.
| |
Collapse
|
40
|
Abstract
There is substantial evidence that the martian volatile inventory and climate have changed markedly throughout the planet's history. Clues come from areas as disparate as the history and properties of the deep interior, the composition of the crust and regolith, the morphology of the surface, composition of the present-day atmosphere, and the nature of the interactions between the upper atmosphere and the solar wind. We piece together the relevant observations into a coherent view of the evolution of the martian climate, focusing in particular on the observations that provide the strongest constraints.
Collapse
Affiliation(s)
- B M Jakosky
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80309-0392, USA.
| | | |
Collapse
|
41
|
Bridges NT, Crisp JA, Bell JF. Characteristics of the Pathfinder APXS sites: Implications for the composition of Martian rocks and soils. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001393] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
42
|
|
43
|
Kraft MD, Greeley R. Rock coatings and aeolian abrasion on Mars: Application to the Pathfinder landing site. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001229] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
44
|
Greeley R, Kraft MD, Kuzmin RO, Bridges NT. Mars Pathfinder landing site: Evidence for a change in wind regime from lander and orbiter data. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001072] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|