When Curiosity went to Mars, it took a penny along with it. The coin -- a 1909 Lincoln penny -- was a nod to geologists’ habit of using a penny in photos of rocks to provide an idea of the object’s size.

That penny, embedded in the rover, is now coated in the dust of Mars. Rather than provide scale, however, the coin was used on this expedition to help calibrate the Curiosity’s camera.

“We’ve just spent a week testing out our 7-foot robotic arm and the camera and spectrometer it holds,” Ashwin Vasavada, deputy project scientist for Curiosity, told the Los Angeles Times in an interview Tuesday morning.

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“Curiosity took some fantastic images of herself with the arm-mounted camera,” he said, “including a set of images showing the undercarriage of the rover and the big, dirty wheels.”

The camera, called the Mars Hand Lens Imager, is an adjustable, color camera that will take extreme close-ups of dirt and pebbles as well as larger, more distant objects, according to NASA. It took a practice shot of the penny just to ensure that everything was in working order.

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Curiosity is now motoring toward Glenelg Intrigue, about a quarter-mile southeast of the rover’s landing site. As The Times has reported, Glenelg is at the confluence of three types of terrain. Scientists on the Mars Science Laboratory mission will look at the spot in an effort to determine “what sort of geological history brings such different types of rock together.”


It’s a detour for the rover, whose goal has been Mt. Sharp, the 3-mile-high mound whose layers may hold clues to the history of Mars. And this may not be the only detour.

On the way to Glenelg, Vasavada said, the team is searching for two things.

“One is a good-sized rock to measure with multiple instruments, in order to cross-compare the results,” he said. “Another is a patch of loose material to practice scooping. We’re likely to take a break from our drive if we find either.”

More on that penny: It was provided by the principal investigator for the arm-mounted camera, Ken Edgett. It’s a 1909 “VDB” penny, according to NASA. 1909 was the first year Lincoln pennies were minted and the centennial of Abraham Lincoln’s birth; VDB are the initials of Victor David Brenner, who designed the penny at President Theodore Roosevelt’s request.


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