Found buried deep underneath the south pole of Mars, a frozen deposit of dry ice contains nearly 30 times more carbon dioxide than scientists previously though to be buried in the area. This color-coded thickness map estimates the size of the deposits -- that large red circle near the middle is the fairly recent dry ice discovery -- based on observations made by the Shallow Subsurface Radar (SHARED) instrument attached to NASA's Mars Reconnaissance Orbiter.
"Red corresponds to about 600 meters or yards thick; yellow to about 400; dark blue to less than 100, tapering to zero," NASA explained. "The background map, in muted colors, represents different geological materials near the southA Fr pole." The amount of carbon dioxide stored in this space changed dramatically as the planet's axis tilts in various directions. Scientists suspect that when the tilt of Mars' axis increases, much of the carbon dioxide stored near the south pole escapes into the planet's atmosphere, causing its mass to increase.
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