NASA's Mars rover Curiosity found soil that bears a striking resemblance to weathered, volcanic sand in Hawaii.
The rover uses an X-ray imager to reveal the atomic structures of crystals in the Martian soil, the first time the technology, known as X-ray diffraction, has been used to analyse soil beyond Earth.
Curiosity found the Martian sand grains have crystals similar to basaltic soils found in volcanic regions on Earth, like Hawaii.
Scientists plan to use the information about Mars' minerals to figure out if the planet most like Earth in the solar system could have supported and preserved microbial life.
The Curiosity rover landed inside a giant impact crater near the Martian equator in August for a two-year, $US2.5-billion mission, NASA's first astrobiology expedition since the 1970s-era Viking probes.
The rover is scouting a site where three types of rock intersect. Next year, scientists plan to drive it over to a five-kilometre mound of sediment, named Mount Sharp, rising from the floor of the crater.
"We're hopeful that once we get into the truly ancient materials on Mount Sharp, we will find minerals that suggest there was a habitable environment of some kind there. We haven't had that happen yet, but we have a lot of time left," said NASA scientist David Blake.