Nov. 4, 2011 at 5:04 PM ET
NASA's Opportunity rover has come across a light-colored line of rocks that could serve as solid evidence for Mars' watery past — and help set the stage for the next Mars mission, due for launch this month.
The formation, nicknamed "Homestake" or "The Vein," showed up in pictures that the rover sent back from the rim of Endeavour Crater early this week. It looks like a few paving bricks, sticking edge up from the surrounding soil. Not all that impressive, but it caught the attention of the rover science team as well as the amateur observers who are following Oppy's every move.
Cornell astronomer Steve Squyres, the principal investigator for the Opportunity and Spirit rover missions, told the Planetary Society's A.J.S. Rayl that he and his colleagues have been keeping an eye on similar light-colored veins of rock for months during Opportunity's dash to the crater rim. Squyres said tracing the veins to find Homestake was a "real triumph of geology."
"These are different from anything we've ever seen with either rover, a completely new thing on Mars, never seen anywhere," Squyres said. "And we're pretty charged up about it."
Stuart Atkinson, a British educator, author and amateur astronomer who has been working up wonderful imagery from the rover missions for years, produced more than a dozen pictures over the past few days documenting Opportunity's surroundings, and particularly what's happening with Homestake. The rover has already been taking a close look at the formation with its microscopic imager.
So what is it? Squyres isn't willing to "hazard a guess" yet, but the speculation is that the rock could point the way to minerals that are linked to Mars' wetter, warmer past. Five years ago, the now-defunct Spirit rover churned up light-colored, silica-rich dirt that had to have been formed in the presence of water.
The Opportunity team has also been looking for phyllosilicates, clay minerals that have already been detected through orbital observations. Such minerals are an important clue to Mars' geological history, since they form in water that's not as acidic as the water that gave rise to Spirit's silica. A less acidic environment would be more hospitable to life.
It may be too early to say what Homestake is, but based on the buzz, it's likely to be something interesting.
More buzz will be stirred up in the weeks to come over the Curiosity rover's upcoming $2.5 billion mission to Mars. The car-sized rover, also known as the Mars Science Laboratory, is due to be launched on Nov. 25 with Mars' Gale Crater as its objective.
Gale Crater should be a candy store for geologists, because it boasts a 3-mile-high (5-kilometer-high) mound of phyllosilicates and sulfates. The composition of the soil at different elevations could help scientists document a billion years of geological and climate history. It could even point to particular eras when Mars was actually habitable by life as we know it. And if those conditions still exist underground ... well, that would be a vein of pure gold for astrobiologists.
By the time Curiosity touches down on the Martian surface next summer, Squyres and his colleagues may well have unraveled Homestake's secrets, and the lessons learned from one rover mission will carry over to the next. Stay tuned...
Tip o' the Log to Discovery News' Jason Major. Special thanks to Stuart Atkinson for sharing his processed images of Opportunity's views.
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