LONDON, Jan. 4 (UPI) — Three billion years ago, Mars was warm enough to sustain lakes that were as wide as 12 miles, scientists at Britain’s Imperial College said.
Satellite images suggest Mars had a warm and wet history during the Hesperian Epoch and then lost most of its atmosphere and became cold and dry, the researchers wrote in a recent issue of the journal Geology.
Images from NASA’s Mars Reconnaissance Orbiter suggest Mars once had lakes as wide as 12 miles along parts of its equator.
Volcanic activity, meteorite impacts or shifts in Mars’ orbit might have warmed the planet’s atmosphere enough to melt ice into lakes. That would have created gases that temporarily thickened the atmosphere, trapping more sunlight and warmth, Imperial College researcher Nicholas Warner said.
“Scientists had largely overlooked the Hesperian Epoch as it was thought that Mars was then a frozen wasteland,” Warner said. “Excitingly, our study now shows that this middle period in Mars’ history was much more dynamic than we previously thought.”
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