Mars rock gives NASA scientists quite a thrill
The more Curiosity gets to know Mars, the more it seems like a big red Earth. Curiosity recently examined what appeared to be an ancient riverbed and conglomerate rocks similar to those at home. Now comes “Jake Matijevic” — a pyramid-shaped chunk of rock that's proved to be a surprise, even to NASA.
The space agency says that Jake, named for a legendary NASA engineer, is unique — unlike any rocks examined before on Mars. And that's saying something. Rovers have examined hundreds of Martian rocks.
When Curiosity team members picked Jake, they were just hoping for a “simple and uniform” rock that would help them compare results from two chemistry instruments.
Jake was the first rock analyzed by the rover's arm-mounted Alpha Particle X-Ray Spectrometer; it was about the 30th on this mission examined by the ChemCam.
“It's a strength of Curiosity to have instruments that use different techniques to get at the same answers,” Ashwin Vasavada, Curiosity deputy project scientist, told the Los Angeles Times on Friday. “But it's also a challenge for the science team — like trying to understand the plot of a story when one person saw the movie and another read the book. We were hoping that Jake M. had a simple plot.”
But NASA got more than it expected. The rock was diverse, surprisingly so.
“Our laser instrument saw a slightly different composition at every point it analyzed,” Vasavada said.
Although there was “broad agreement between it and another spectrometer that the robotic arm held against the rock, there also are some discrepancies yet to be understood. The differences between the two instruments are telling us that the rock contains a diversity of minerals down to the finest scales.”
The results so far reveal a good match, Vasavada said, for a type of Earth rock.
On Earth, these kind of rocks form from relatively water-rich magmas that have cooled slowly at raised pressures, said Edward Stolper.
The rock is “widespread on Earth, on oceanic islands such as Hawaii, and St Helena, and the Azores; and also in rift zones like the Rio Grande and so forth. So, again, it's not common, but it's very well known,” the mission co-investigator from the California Institute of Technology, Pasadena, told reporters.
Jake Matijevic also had an interesting, weathered appearance that drew attention.