Scientists are mystified by the latest image the rover returned to Earth

Sep 15, 2012 11:18 GMT  ·  By

A rocky outcrop called Kirkwood, which the Mars Exploration Rover (MER) Opportunity reached last week, revealed a series of spherical objects the likes of which the robot has never seen during its mission. This says a lot, considering the machine landed on Mars in January, 2004.

Spherules, such as the iron-rich blueberries that Opportunity found at its landing site, are not uncommon on the Red Planet, but the new type of spherical objects has never been seen before. Each of them is around 3 millimeters (1/8 inches) in diameter.

“Kirkwood is chock full of a dense accumulation of these small spherical objects. Of course, we immediately thought of the blueberries, but this is something different. We never have seen such a dense accumulation of spherules in a rock outcrop on Mars,” Steve Squyres says.

The expert, who is based at the Cornell University, in New York, is the principal investigator of Opportunity's science data, experts at the NASA Jet Propulsion Laboratory say.