How Mars Can Help Us Understand ‘Marginal’ Exoplanets

We’ve discovered large numbers of small rocky exoplanets, but they’re at such great distances that habitability is extremely difficult to determine. New research suggests than since Mars is on the edge of being habitable, studying it in detail can shed light on rocky exoplanets. If we can understand things like tectonic activity and atmospheric escape on Mars, we can understand how they may play out on rocky exoplanets.