Hot Science - Cool Talk # 38 The 2004 Mars Exploration Rover Mission: Evidence for Water and Prospects for Life Dr. John Grotzinger October 13, 2005 Produced by and for Hot Science - Cool Talks by the Environmental Science Institute. We request that the use of these materials include an acknowledgement of the presenter and Hot Science - Cool Talks by the Environmental Science Institute at UT Austin. We hope you find these materials educational and enjoyable. The 2004 Mars Exploration Rover Mission: Evidence for Water and Prospects for Life John Grotzinger on behalf of MER Athena Science Team Mars Science Strategy: Follow the Water! Common Thread LIFE CLIMATE Mars Science Strategy GEOLOGY HUMAN The Athena Science Payload Remote Sensing Package Pancam Mast Assembly (PMA) Pancam Mini-TES Magnetic The Athena Science Payload Properties Experiment In-Situ Package Instrument Deployment Device (IDD) Microscopic Imager Alpha Particle X-Ray Spectrometer Mössbauer Spectrometer Rock Abrasion Tool The Team The Team Mars Pathfinder Mars Pathfinder The MER Rover Wrap it up and cram it in…… Wrap it up and cram it in… The Three Challenging Mission Phases Launch & Cruise Entry, The Three Challenging Descent & Mission Phases Landing Egress & Surface Operations Video by Dan Mass Opportunity at Meridiani Planum 2000 km Meridiani Gusev Hematite: Mineralogic Beacon o Hematite Distribution Map from Tes Data 5 N 0 o 6 S o o 10 W 0 2 E 0% 15% hematite (Figure based on Christensen et al., (2001) JGR, v. 106(E10), Plate 2, p.23,877.) Meridiani Landing Site Hole in One Eagle Crater Backshell and Parachute Backshell and Parachute You are here You are here A Martian Eclipse Short-Timescale Temperature Excursions 1 Red = hot 0.8 Purple = cold 0.6 0.4 Red to purple is 2 K (degrees Kelvin) Height Above Surface (km) Surface Above Height 0.2 0 21 22 23 24 25 26 27 28 29 Minutes past 1000 hours (sol 12) • Largest temperature variations confined to lowest 100 meters or so • Appears that temperature perturbations propagate upward Dust Devils Dust Devils Spirit: View from Lander 5 metres Opportunity: View from Lander 5 metres The first rock investigated by Opportunity Schematic representation of the Mössbauer Spectrometer Mössbauer Spectrum of El Capitan: +1 Meridiani Planum Jarosite: (K, Na, X )Fe3(SO4) (OH)6 Mössbauer Spectrum of El Capitan Rio Tinto, Spain Andy Knoll Spherules Spherules 5 mm The “Berry Bowl” Mössbauer on the Berry Bowl Sediment Bedforms (e.g. Ripples) Sediment Bedforms Ancient Terrestrial Ripples: 1.4 Billion Years Old Ancient Terrestrial Ripples Ripple Cross-Bedding in 3D Ripple Cross-Bedding in 3-D Bedforms in Flowing Water 2.0 Antidunes Upper Plane Beds ) 1 - 1.0 Lower Dunes Plane 0.6 Beds Bedforms in Flowing Water Ripples No Sediment Mean Mean flow velocity (m sec Movement 0.2 V. Fine Sand V. Coarse Sand 0.1 0.5 1.0 2.0 Median grain diameter (mm) Southard and Bouchwal,1990 Current Ripples in Water 6 hours of ripple migration Image is 60x40 cm Current Ripples in Water Flume experiments by Dave Rubin and Jon Nelson, USGS Current Ripples in Cross Section Simulation by Dave Rubin, USGS Festoon Cross-Bedding on Earth Festoon Cross-Bedding on Earth Festoon Cross-Bedding on Mars Festoon Cross Festoon Bedding on Mars on Bedding - Burns formation (Endurance crater) 2.0 m formation Burns Burns 7 Interdune/Playa Festoon Cross-lamination Wavy Bedding Burns Stratigraphy Translatent Strata 6 Lower Unit Whatanga Contact Zone of Recrystallization 5 Capillary Fringe of Water Table? Eolian Sand Sheet 4 Translatent Strata Low-Angle Strata Burns Stratigraphy Lower Unit 3 Wellington Contact Deflation Surface 2 Water Table Controlled? Eolian Dune Field Cross-Bedded Sandstone 1 Lower Unit m Modern Sand Dunes on Mars Modern Sand Dunes on Mars ~ 50 cm Interdune Surface Interdu ne Surfac e Interdune Deflation Surface Interdune Deflation Surface Modern Mars Analog: Um Asamin Modern Mars Analog Formation of evaporite salts Modern Interdune Depression Modern Interdune Depression Endurance Chemostratigraphy ~ 50 cm Ratio to surface rock average Depth in crater Depth Changes Down Section: Texture Ontario Diamond Jenness • Meridiani environment appears to have been acidic, hypersaline, and only intermittently wet. • Life exists at such extremes on Earth. • But Meridiani data suggest potential challenges to origin as well as persistence of life. Rio Tinto Extremophiles Andy Knoll The Good News • Evidence of any life that might have existed might well be preserved in chemical sediments and concretions. • Chemical and textural details of Meridiani salts and iron oxides likely to reveal much about environmental history. • All this favors Meridiani Planum as a target for sample return. Andy Knoll Summary • Rovers have: – Operated for over 1200 days – Returned over 100,000 images – Analyzed dozens of rocks and soils Summary • Evidence for water: – Mössbauer detection of jarosite – Crystal molds, concretions, diagenesis – Festoon ripple cross-bedding – Stratigraphic succession of environments Summary • Prospects for Life: – Preservation potential is good – But did life originate under such extreme conditions? Dr. John Grotzinger Fletcher Jones Professor of Geology California Institute of Technology John Grotzinger is a field geologist interested in the co-evolution of surficial environments and life on Earth and Mars. His research addresses the chemical development of the early oceans and atmosphere, and the environmental context of early evolution. Field mapping studies are the starting point for more topical laboratory-based studies involving geochemical, paleontological, and geochronological techniques. Currently, his research is focused on the reconstruction of environmental conditions associated with the Cambrian radiation of animals in Oman, Namibia and Siberia. In 2004, he served as a member of both the Geology and Long Term Planning Groups for the Mars Exploration Rover mission. .
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