Spirit rover data reveals widespread ancient water on Mars

A new analysis of data collected more than two decades ago by NASA's Spirit rover has uncovered significant new evidence that liquid water was widespread across ancient Mars. The research, led by Professor Paulo de Souza of Edith Cowan University in Australia, combined hundreds of measurements taken by the rover between 2004 and 2010 to create the most detailed iron-mineral profile yet assembled for Martian soil.

De Souza and his team focused on data from 32 undisturbed soil sites inside Gusev Crater, where Spirit landed in January 2004. Their work revealed widespread traces of crystalline hematite and altered magnetite, minerals that typically form when rocks interact with liquid water. The presence of hematite is considered a particularly strong indicator of past water activity. De Souza stated that one of the most important discoveries was finding this mineral in ordinary Martian soil, suggesting not only that water was present, but that significant areas of Mars may have once been covered by water.

The findings are significant because individual spectrometer readings taken by Spirit during its mission were not detailed enough to definitively identify these minerals in small...