Dating a rock Freechat cam to cam canada
"That gives us some idea about why the environment looks like it does and it gives us an idea of where to look for rocks that are even less exposed to cosmic rays," and thus are more likely to have preserved organic molecules, Farley says.
Curiosity is now long gone from Yellowknife Bay, off to new drilling sites on the route to Mount Sharp where more dating can be done.
The smooth floor of Yellowknife Bay is made up of a fine-grained sedimentary rock, or mudstone, that researchers think was deposited on the bed of an ancient Martian lake.
In March, Curiosity drilled holes into the mudstone and collected powdered rock samples from two locations about three meters apart.
The exposure of rock in Yellowknife Bay has been caused by wind erosion.
Farley had the idea of performing the experiment on Mars using the SAM instrument.However, shortly before the rover left Earth in 2011, NASA's participating scientist program asked researchers from all over the world to submit new ideas for experiments that could be performed with the MSL's already-designed instruments. Findings from the first such experiment on the Red Planet—published by Farley and coworkers this week in a collection of Curiosity papers in the journal —provide the first age determinations performed on another planet.The paper is one of six appearing in the journal that reports results from the analysis of data and observations obtained during Curiosity's exploration at Yellowknife Bay—an expanse of bare bedrock in Gale Crater about 500 meters from the rover's landing site.Cosmic rays are known to degrade the organic molecules that may be telltale fossils of ancient life.However, because the rock at Yellowknife Bay has only been exposed to cosmic rays for 80 million years—a relatively small sliver of geologic time—"the potential for organic preservation at the site where we drilled is better than many people had guessed," Farley says.
"MSL instruments weren't designed for this purpose, and we weren't sure if the experiment was going to work, but the fact that our number is consistent with previous estimates suggests that the technique works, and it works quite well."The researchers do, however, acknowledge that there is some uncertainty in their measurement.