For a while, the planet (Earth) was abuzz with speculation about something found on Mars that was âfor the history books.â As we now know (and I warned you, folks), this was nothing more than speculation: A reporter ran away with a quote by a Curiosity scientist who simply meant that the overall mission would make its mark on planetary scienceÂ history.
At the time, when rumors were flying, some people were thinking âorganic molecules.â These are complex molecules based on carbon, which are the basic building blocks of life as we know it. We also know thereâs frozen water all over Marsâanother necessary ingredient for lifeâso they idea of finding organic compounds is exciting.
At a press conference today, scientists talked about the latest results from Curiosity, and they put the kiboshâtemporarily, at leastâon organics.
âWe have no definitive detection of Martian organics at this point, but we will keep looking in the diverse environments of Gale Crater,â said Curiosity scientist Paul Mahaffy. He is the Principal Investigator (top banana) on the SAM (Sample Analysis at Mars) instrument, a device that can perform detailed analysis of the chemistry and composition of surface samples scooped up by the rover.
This result isnât terribly surprising, actually. The Mars Phoenix Lander set foot near the red planetâs north pole a few years ago and found a high level of perchlorates, a reactive chemical that can destroy carbon-based compounds. That was a long way from where Curiosity touched down, but it did show us that organic molecules may be in trouble on Mars. And Curiosity found evidence of perchlorates at its location as well.
Thatâs too bad, but not devastating. For one thing, the chemistry of the surface changes with depth, and we have literally only scratched the surface. And weâve still only examined a tiny, tiny fraction of Mars. Thereâs a lot of real estate yet to explore.
Iâll note that a very small signal from what may be simple organic molecules was found, but it could be something left over from Earth still inside the rover. Thatâs why in the quote above Mahaffy said, âno definitive detection.â We can be sure organics arenât abundant on Mars in this area, but time will tell.
Still, what Curiosity did find was pretty interesting. Chlorine, sulfur (together comprising up to 10 percent of the samples taken), even some water molecules (not muchâweâre not talking ponds or snowfields, just some moleculesâbut more than expected). It also is seeing glassy compounds and other minerals typical of volcanic emissions.
The good news Iâm seeing here is that Curiosity works, and works great. I know some people will be disappointed with the news of what it found, but cripes: We have a one-ton nuclear powered mobile chemistry lab roving around an ancient riverbed of another planet!
That very fact gives me chills. Oh, the things we humans do.