1 there’s lots of evidence for water on mars…in the past river beds and teardrop-shaped...
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There’s lots of evidence for water on Mars…in the past
• River beds and teardrop-shaped “perched” craters.
• Lake beds• Minerals have been found that only form under
water.• Outflow Channels• Sedimentary layers in the walls of the Valles
Marineris and many craters.• Gusev Crater!
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This is the shore ofan ancient lake.
Notice the layeringin the rocks!
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These little nodules, “blueberries”, are madeof the mineral hematite that usually formsonly under water.
The blueberrieswere found nearMeridiani Planum,the landing site ofNASA’s MarsExploration RoverOpportunity.Image credit: NASA
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Similar hematite noduleshere on earth.
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Obvious layeringin the rocksnear the landingsite of NASA’sOpportunityRover.
Image Credit: NASA
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Finally…Gusev CraterIn 2004, NASA’s roverSpirit landed inside GusevCrater. This crater quicklyshowed that it had oncebeen full of water.
It’s connected by a valleyto an outflow channel, andwas probably filled withwater and sediment duringthe catastrophic flooding.
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What about recent water on Mars?
• There is some possible evidence for recent water on Mars:– Gullies in the walls
of some craters mighthave been formed when water ran down the crater walls under layers of frost or ice. Credit: Malin Space Science Systems, MGS, JPL, NASA
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13Newton Basin 100
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Where Did the Water Go?
• Today, liquid water can’t exist long on the surface of Mars due to the low temperature and low atmospheric pressure.
• Loss of magnetic field ... atmospheric erosion … water lost to space.
• Some water is still in the polar ice caps and may still exist in permafrost.
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