ECU Joondalup Professor makes breakthrough in decades-old Mars rover data

A researcher from Edith Cowan University in Joondalup has uncovered new evidence supporting the idea that large parts of Mars were once covered by water.

More than 20 years after NASA’s Spirit rover landed on Mars, ECU Deputy Vice-Chancellor (Research) Professor Paulo de Souza, who worked on NASA’s Mars Exploration Rover mission, has identified previously undetected mineral clues in the rover’s data.

Professor de Souza found traces of hematite and altered magnetite, which are two iron-rich minerals that can form when rocks interact with water.

He made the discovery by re-examining observations collected by the Spirit rover during its more than 2000-day mission on Mars between 2004 and 2010, analysing data from 32 undisturbed soil sites across Gusev Crater.

Scientists had previously believed little to no hematite was present in these soils, but the new analysis suggests it was present in quantities too small for individual rover measurements to detect.

“The original rover observations were limited by time, power and the gradual ageing of the instrument used to collect the data,” Professor de Souza said.

“Many measurements were not detailed enough on their own to identify minerals present in very small quantities.

“By bringing the data together and analysing it in a new way, we were able to reveal information that had been hidden for years.”

By combining hundreds of individual measurements, Professor de Souza created what researchers describe as the most detailed iron-mineral profile of typical Martian soil ever produced.

“One of the most important discoveries was finding crystalline hematite in ordinary Martian soil,” he said.

“This mineral’s widespread presence suggests not only that water was present, but that significant areas of Mars may have once been covered by water.”

Researchers believe the findings also support the theory that much of the Martian surface is covered by a similar layer of dust and soil, built up over millions of years by wind, temperature extremes and dust storms.

NASA’s Spirit rover launched from Cape Canaveral in Florida in June 2003 and landed on Mars in January 2004.

Originally designed to operate for just 90 Martian days, the rover far exceeded expectations, remaining active for 2208 sols, more than 20 times longer than NASA had expected.

During its mission, the rover, which was about the size of a golf cart and seven times heavier, searched for a range of rocks and soil types while looking for clues to past water activity on Mars.

In May 2009, the rover became trapped in soft sand. After months of unsuccessful attempts to free it, NASA announced in January 2010 that Spirit was unlikely to be recovered and would instead continue operating as a stationary science platform.

Communication with the rover was eventually lost in March 2010, and NASA officially declared the mission over in May 2011.

Professor de Souza said his findings, published last month in the journal article “A Consolidated Mössbauer Spectrum for Undisturbed Soils from Gusev Crater, Mars”, shows that older space mission data can still lead to new discoveries.

“This work shows that important discoveries are not always made by collecting new data,” he said.

“Sometimes they come from looking at existing data with fresh eyes and better analytical techniques.”