Was Loss of Water from Mars Destined from the Start?

James Maynard
Sep 23 · 4 min read

The loss of water from Mars is a massive issue — or, rather, an issue of a lack of mass.

A look at what Mars may have looked like, long ago, covered in water. Image credit: ESO/M. Kornmesser/N. Risinger/Skysurvey.org

Billions of years ago, Mars was a watery world, more akin to Earth than the desert planet we see today. The Red Planet — just half the diameter of Earth and 10 percent of our mass — would have made a wonderous sight in the Solar System. Yet — however cute its diminutive nature might…