Mars Rocks Reveal Some Early Surprises
Deciphering the "fire hose of data" coming from Mars will take years, but early work is providing clues to the overriding mystery of whether Mars once was capable of hosting life.
Conditions on Earth and Mars are thought to have been similar in the planets' early stages, and during that time, primitive life emerged on Earth. Was Mars just as hospitable?
In their first efforts to assemble the early Mars puzzle, Pathfinder scientists are asking some basic questions: What is Mars made of? What can its rocks tell us about its early history? How do the findings compare with those of earlier missions to Mars?
For answers, they're turning to clues captured in the shapes, textures, colors, and chemical composition of the rocks and soil around Pathfinder's landing site. What they are learning so far amounts a few pieces of the puzzle turned over, and they've made some tentative attempts to put a few of them together.
Earlier this week, for example, Sojourner spent a frigid Martian night with its chemical detector bumped up against "Barnacle Bill," a hefty rock nearly 8 inches across.
When University of Tennessee geologist "Hap" McSween looked at the results, "I was real surprised." Barnacle Bill, it turns out, contains a chemical mix that resembles Earthbound volcanic rocks known as andesites, first discovered in the Andes Mountains. Its chemical mix also is similar to that of rocks on Earth that have been recycled several times between the crust and mantle before finally reaching the surface.
"I didn't expect to see rocks of this composition on Mars," Dr. McSween says. Follow-up studies with the lander's camera also support the notion of a volcanic origin for Barnacle Bill.
Researchers have sent Sojourner to sniff out a rock nicknamed "Yogi," which resembles the hind end of a bear. Yesterday, they expected to send the rover to look at two whitish lumps, "Casper" and "Scoobie Doo."