Quick photo insights
Outside of Space Ponder, I usually photograph Earth landscapes, but I've never seen anything like this before.
In this photo, we see many shallow pits in the bright cap of carbon dioxide ice, often called the "Swiss cheese terrain." There's also a deeper, circular hole that goes through the ice and dust, which could be an impact crater or a collapse pit.
These pits form because of a cool Martian phenomenon. The cap is made mostly of carbon dioxide ice, which can sublimate – going directly from solid to gas – when heated by the Sun.
The "cheese" itself isn't very deep, with estimates suggesting it's only about 8 meters (26 feet) thick. Underneath lies another layer, this time of water ice. The whole system is dynamic, with some areas growing new CO2 frost in flatter regions while the pits continue to expand.
This two-layered structure supports the idea that Mars once had a much thicker and wetter climate.
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