Work in the Chilean desert by Arizona State University scientists has reopened debate regarding the biological origins of Martian silica fragments found in 2007 — and strengthened the case for life on Mars billions of years ago.

NASA’s Spirit rover churned up the opaline silica deposits as it explored the Columbia Hills area of Mars’s Gusev Crater.

Read/listen to my full story at KJZZ’s Arizona Science Desk:
Silica Nodules In Chile Argue For Ancient Life On Mars