Using a laser and X-rays, the NASA rover Curiosity identified a rock named Jake as a form of basalt, similar to volcanic rocks found in ocean-island settings on Earth.
The Martian rock, a form of basalt, has a composition very similar to volcanic rocks found in ocean-island settings such as Hawaii and the Azores, as well as in rift zones – regions where Earth's continents split and begin separating into separate land masses.
The rock, named Jake Matijevic for a key member of the rover engineering team who passed away shortly after Curiosity arrived on the red planet, can form in a number of ways, says Edward Stolper, provost of the California Institute of Technology in Pasadena and a member of Curiosity's science team.
On Earth, this kind of rock forms as magma cools and crystallizes under relatively high pressure and with relatively high concentrations of water dissolved in the magma, he explains, adding that when the molten leftovers erupt, they tend to erupt explosively.
The release, during volcanic eruptions, of water dissolved in magma is one pathway for water vapor – a greenhouse gas – to enrich and warm a planet's atmosphere. Indeed, Curiosity's mission aims to see if Gale Crater ever could have hosted microbial life – a prospect that would have required the presence of liquid water in the crater.