Why Mars Life Science Goals Lucero Flores Kevin

Why Mars - Life Science Goals Lucero Flores, Kevin Jin, Kevin Wilde

Did life originate on Mars? • More recent idea: • Microbial life originated on Mars • Impact on Mars sends meteorites into space • Meteorite brings life to Earth • Low escape velocity http: //www. lpi. usra. edu/publications/slidesets/redplanet 2/slide_33. html

Did life originate on Mars? • 1972 • Period early in history of Mars when “global temperatures were not far from the freezing point of seawater and … the origin of life may have occurred. . . as it did on primitive Earth in the same period. ” 1 Sagan, Carl, and George Mullen. “Earth and Mars: Evolution of Atmospheres and Surface Temperatures. ” Science, vol. 177, no. 4043, 1972, pp. 52– 56. 1 http: //www. dailygalaxy. com/my_weblog/2017/03/solar-winds-morphed-mars-from-awater-based-life-potential-habitat-into-a-frigid-desert-world. html

Did life originate on Mars? • 1996 • Abundant evidence of water erosion on Mars • Mars is volcanically active • “The combination of water and volcanism must have commonly resulted in hydrothermal environments similar to those in which grow the most primitive terrestrial life-forms. ” 1 1 Carr, Michael H. “Water erosion on Mars and its biologic implications. ” Endeavour, vol. 20, issue 2, 1996, pp. 56 -60.

Did life originate on Mars? • 2001 • “. . . early Mars, with then-vigorous volcanism, may have been a kinder, gentler habitat than Earth” 1 • “. . . life may have existed earlier on Mars or even on Venus or an outer moon and been translated to Earth by meteorite. We still have little idea how, when or where life began. ” 1 Nisbet, E. G. , and N. H. Sleep. “The habitat and nature of early life. ” Nature, vol. 409, no. 6823, 22 Feb 2001, pp. 10831091 1

Did life originate on Mars? • 2013 • Oxidized molybdenum helps organic materials form life • 3 billion years ago, Earth had very little oxygen so oxidized molybdenum not available • But scientists believe it was available on Mars • “It’s yet another piece of evidence which makes it more likely life came to Earth on a Martian meteorite rather than starting on this planet. ” 1 1 Benner, Steven A. “Planets, Minerals and Life’s Origin. ” Goldschmidt 2013 Conference.

Did life originate on Mars? • Did life exist on Mars in past? • Was it brought to Earth or did life on Earth develop separately? • Both of these questions still open • Mission to Mars could provide evidence of life in past to help answer these questions http: //mediachannel. nationalgeographic. com/media/uploads/photos/content/photo/2016/08/29/MA RS_Helmets_DL. jpg

What are indicators life? Did/does life exist on Mars? There is evidence that Mars had the characteristics of a habitable planet. 3 main categories that point to life existing in the past are evidence for Water https: //static. pexels. com/photos/62307/airbubbles-diving-underwater-blow-62307. jpeg Heat + Plate Tectonic Activity https: //s-media-cacheak 0. pinimg. com/originals/15/42/b 2/1542 b 2 e 0 338 dff 64 a 97 b 8173 d 5 e 7382 b. jpg Violent Impacts https: //www. universetoday. com/wpcontent/uploads/2009/02/blastofffrommarse 1417645954948. jpg

Evidence for water on Mars • Veins: are they gypsum ? • High (maybe pure) Ca. SO 4 • Evidence of hydration leads scientists to believe veins are gypsum • Topography: • River channels • Deltas • Iron carbonate • Neutral water chemistry Whipple Lecture: P 33 F. Clues to a Hot, Wet and Violent Ancient Mars - 2012 AGU Fall Meeting

Evidence for water on Mars • Mission scientists have described the rock as “full of zinc and bromine, elements that, at least for rocks on Earth, would be suggestive of geology formed with heat and water, ” reports The Age. http: //www. huffingtonpost. com/2011/09/02/mars-rover-nasa-rock_n_947044. html

Evidence for water on Mars • Mineralogy: • Goethite • Hematite • Heat + Steam vents A Re-examination of the Stability of Goethite on Mars JAMES B. POLLACK 1

Evidence that Mars was a hot and active planet • Evidence includes: • Volcanos • Basalt lavas interacting with acidic volcanic fumes precipitate silica • Rocks: • Evidence of silica in soil and rocks • Silica in deep Mars - hot water, neutral p. H below surface, picks up silica, rises, cools Whipple Lecture: P 33 F. Clues to a Hot, Wet and Violent Ancient Mars - 2012 AGU Fall Meeting

Evidence that Mars was a hot and active planet • Plate tectonics: • Ridges, mountains, volcanoes, plateaus, valleys, lake basins, deltas, dry river channels like on Earth • Being a hot planet is important for convection, plate tectonics, life. Whipple Lecture: P 33 F. Clues to a Hot, Wet and Violent Ancient Mars - 2012 AGU Fall Meeting

Evidence that Mars was a violent planet • Diversity of geochemistry indicates multiple impacts • Mixed grain rock sizes throughout Mars • Rocks rich in nickel (impacts) • Suevite breccia and lithic breccia

What are indicators life? Did/does life exist on Mars? If life did/does exist on Mars, impacts → ejecta → life from Mars can travel to other planets. https: //www. universetoday. com/wp-content/uploads/2008/10/impact_mars. jpg

Previous Findings • ALH 84001 • Meteorite in Antarctica from Mars 1 • ~4 billion years • Contained organic compounds (not necessarily from life) • Magnetite 2 Mc. Kay, David S. , et al. “Search for Past Life on Mars. ” Science, vol. 273, 1996, pp. 924– 930. 2 Golden, D. C. , et. al. “A simple inorganic process formation of carbonates, magnetite, and sulfides in Martian meteorite ALH 84001. ” American Mineralogist, vol. 86, 2001, pp. 370– 375. 1 https: //www. nasa. gov/images/content/652612 main_pia 00289 -946. jpg

ALH 84001 Microscopic Fossils? http: //web. archive. org/web/20051218192636 im_/http: //curator. jsc. nasa. gov/antmet/mars mets/alh 84001/images/ALH 84001 -EM 1. jpg

Previous Missions • 40 spacecraft to Mars, no fossils found • Curiosity • Once had more atmospheric oxygen (manganese oxide) • Chemicals needed for life (sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon) • Minerals from liquid water https: //mars. nasa. gov/news/nasa-rover-findings-point-to-a-more-earth-like-martian-past http: //www. space. com/20396 -mars-rover-curiosity-big-discoveries. html http: //www. newyorker. com/magazine/2013/04/22/the-martian-chroniclers

What might a human mission accomplish? • More adaptable and efficient • Observe objects in natural setting and minimize contamination risk • Dig deeper and identifying fossils • Understand challenges of surviving on Mars for potential colonization

Mars 2020 https: //mars. nasa. gov/mars 2020/mission/science/ https: //mars. nasa. gov/mars 2020/images/PIA 14839 -full 2. jpg