Jimmy Westlake: Awaiting the big news from Mars
November 26, 2012
NASA's intrepid robotic explorer Curiosity has made a significant discovery this month in the red sands of Mars, but NASA officials are being very tight-lipped about what that discovery is. Scientists want to make sure their data are correct before announcing the discovery to the world in a week or so.
The blogosphere has been abuzz with speculation about what Curiosity has found ever since NASA scientist John Grotzinger titillated us with his announcement in a Nov. 20 NPR interview that Curiosity had made a discovery that is "one for the history books." That sounds big. Just how big could it be?
The Curiosity rover made a spectacular landing inside of the Gale crater in August. Since then it has been puttering around close to its landing site testing out all of its systems before heading to the real target a few kilometers away — the sedimentary clay layers exposed on the flanks of Mount Sharp. In the past week, Curiosity took its first scoop of the Martian soil and dropped it into its SAM instrument (Sample Analysis at Mars). The exciting discovery apparently has something to do with what SAM detected in the soil sample.
Here is my speculation about the big news from Mars:
At the low end of the "one for the history books" spectrum would be the discovery of organic chemicals or chemistry in the Martian soil. Earlier analysis by NASA's Viking landers in 1976 failed to detect any organic (carbon-based) materials in the soil at their landing site. It is difficult, if not impossible, to imagine the possibilities of life as we know it without these organic chemicals, so the discovery of organic chemicals in the Martian soil would definitely be big news. But the presence of organic chemicals does not necessarily mean biological activity.
At the high end of the "one for the history books" spectrum would be the discovery of living organisms on Mars. Curiosity's instruments are not specifically designed to detect life, only the elements and conditions for life. But if the data were robust enough, they might strongly suggest the presence of living organisms or fossilized organisms. Either one of these conclusions indeed would be earth shattering. Why?
Life is the only remaining characteristic of Earth that makes it absolutely unique in the universe. We no longer think that Earth is located in or near the center of the universe, in a physical sense, but the presence of carbon-based life makes it the biological center of the universe. Were we to discover life — even fossilized life — on another world, it would remove the last remaining pillar elevating Earth above all other planets. The discovery would be so significant in terms of human thought that future generations might well divide human history into "Before Extraterrestrial Life Was Discovered" and "After Extraterrestrial Life Was Discovered." It's that big.
I sincerely hope NASA scientists aren't overhyping some obscure geologic discovery in the Curiosity data. If so, they are going to pay a heavy price for creating the wave of high expectations that was raised with their early pre-announcement. I, like the rest of the world, await this "history book" discovery with bated breath.
Professor Jimmy Westlake teaches astronomy and physics at Colorado Mountain College's Alpine Campus. Check out Westlake's astrophotography website at http://www.jwestlake.com.