Mars Has Bizarre "Swiss Cheese" Terrain. You can Thank Water, Carbon Dioxide and 500,000 years of Climate History for That

Seen from space, regions of Mars around the south pole have a bizarre, pitted “Swiss cheese” appearance. These formations come from alternating massive deposits of CO2 ice and water ice, similar to different layers of a cake. For decades, planetary scientists wondered how this formation was possible, as it was long believed that this layering …