A couple of weeks ago, word leaked out from the Curiosity team that one of the rover's instruments had found something "earthshaking." Immediately people began speculating that the NASA mission had discovered organic compounds, which would be pretty good proof of life on Mars. The news spread quickly, and NASA began backpedalling, hoping to manage expectations, instead saying the results were "interesting."
Fast forward to earlier today, when Curiosity's main scientists held a press conference about their findings so far. The rover had scooped some soil, they reported, which turned out to be completely normal Martian soil. Sort of. This batch also contained chloromethanes of various types (one, two, and three chlorine atoms). The chlorine part wasn't exciting—Phoenix, a previous rover, also discovered perchlorates—but the methyl part was. Compounds with methyl groups often indicate the presence of methane, which can be a telltale byproduct of living things.
Does this mean we finally found life on Mars? Maybe, or maybe not. The rover "has made detection of organic compounds, we just don't know if they're indigenous to Mars," said John Grotzinger, project scientist at the Mars Science Laboratory. In other words, the finding is "interesting" and definitely not "earthshaking."
Underwhelmed? Welcome to science in real time. Tests must be painstakingly run and rerun. Results must be compiled, questioned, and interpreted. All of that takes a long time, which Grotzinger emphasized at the press conference.
"Curiosity's middle name is patience, and we all have to have a healthy dose of that," he added. (Maybe someone should have reminded them of that a few weeks ago.)
There are still a bevy of tests that scientists must perform before they can determine whether the detected organic compounds are indeed from Mars and were not deposited there by an asteroid, for example. Once that is confirmed, then they have to determine whether those compounds were created by a living thing and are not just the byproduct of a more prosaic chemical reaction. The good news is that Curiosity is only a few months into its two-year mission. There's still plenty of time.
Today's announcement is slightly more intriguing than a standard early mission update. The results are exciting, but not that exciting because there's still lots more work to be done. Stiill, Curiosity scientists are hopeful. After this first round of tests are complete, the rover will start its trek up Mount Sharp, which may have more tantalizing, or perhaps more definitive, secrets locked within its ancient rocks.
"We've been at the gas station, gassed it up, checked the oil," Grotzinger said. "We're going to kick the tires around a little bit, but then we're ready for our trip. And that's when our science mission of exploration really gets into full gear."