This low-angle self-portrait of NASA's Curiosity Mars rover shows the vehicle at the site from which it reached down to drill into a rock target called "Buckskin" on lower Mount Sharp. | NASA/JPL-Caltech/MSSS

The Case for Sending the Search for Life on Mars Underground

A leading researcher suggests the Red Planet’s harsh atmosphere means its surface might not be the most likely place to find the building blocks for life.