About 4.3 billion years ago, up to 20 percent of Mars was covered by an ocean that reached about a mile in depth, according to scientists from NASA's Goddard Space Flight Center. The polar ice caps today contain the 13 percent of that ocean that didn't evaporate into space when Mars' atmosphere largely disappeared.
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Dark energy data suggest Einstein was rightSpeed Read Albert Einstein's 1915 theory of general relativity has been proven correct, according to data collected by the Dark Energy Spectroscopic Instrument
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New DNA tests of Pompeii dead upend popular storiesSpeed Read An analysis of skeletal remains reveals that some Mount Vesuvius victims have been wrongly identified
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NASA's Europa Clipper blasts off, seeking an oceanSpeed Read The ship is headed toward Jupiter on a yearslong journey
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Detailed map of fly's brain holds clues to human mindSpeed Read This remarkable fruit fly brain analysis will aid in future human brain research
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Blind people will listen to next week's total eclipseSpeed Read While they can't see the event, they can hear it with a device that translates the sky's brightness into music
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Melting polar ice is messing with global timekeepingSpeed Read Ice loss caused by climate change is slowing the Earth's rotation
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An amphibian that produces milk?speed read Caecilians, worm-like amphibians that live underground, produce a milk-like substance for their hatchlings
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Jupiter's Europa has less oxygen than hopedspeed read Scientists say this makes it less likely that Jupiter's moon harbors life
