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The rotational axis of Mars is currently tilted by about 25 degrees, very similar to that of the Earth (at 23.4 degrees). However, while Earth's axial tilt (also known as "obliquity") tends to change very slightly over time (almost 3 degrees in 40,000 year-cycles), the obliquity of Mars is much more chaotic and varies widely from 0 to almost 60 degrees! The fact that it is currently similar to that of the Earth is merely a coincidence. Currently, water-ice is stable on the Martian surface only in the polar regions. However, during times of "high obliquity," that stability shifts towards the e…
