While its sister rover Spirit has garnered most of the attention lately, NASA's other Mars traveler, Opportunity is chewing up Martian dirt and unearthing the mineral and chemical makeup of the red planet.
NASA scientists said this week the rover uncovered "one of the coolest things Opportunity has found in a very long time:" a dark, basketball-sized rock known as "Marquette Island."
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According to NASA the Marquette Island rock is a coarse-grained rock that indicates it cooled slowly from molten rock, allowing crystals time to grow. Such composition suggests it originated deep in the crust, not at the surface where it would cool quicker and have finer-grained texture, NASA stated.
The rock's interior contains more magnesium than in typical Martian basalt rocks Spirit has studied, according to NASA. Researchers are determining whether it might represent the precursor rock altered long ago by sulfuric acid to become the sulfate-rich sandstone bedrock that blankets the region of Mars that Opportunity is exploring, NASA stated.
Opportunity's rock abrasion tool - which was built by Honeybee Robotics Spacecraft Mechanisms -- was used to grind away some of the rock's surface and expose the interior. This was the 38th rock Opportunity has ground into, and one of the hardest, NASA stated.
According to NASA, the Opportunity rover is about 30% of the way on a 12-mile trek begun in mid-2008. It is en route toward a large crater known as Endeavour.
The rover traveled 3.3 miles in 2009, farther than in any other year on Mars, NASA stated. Overall Opportunity has driven more than 11 miles and returned more than 133,000 images. The rover has made numerous discoveries, including the first mineralogical evidence that Mars had liquid water, according to the space agency.
Since landing on the red planet in January 2004 Spirit and Opportunity have explored Mars for five years, far surpassing their original 90-day mission, NASA said.
Opportunity's sister rover, Spirit you'll recall is mired in a sandtrap on the opposite side of the red planet. Spirit has two broken power wheels and the space agency's scientists face the unenviable task of trying to get the stuck spacecraft out of the sand before Martian winter sets in and pretty much ends the spacecraft's life.
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