NASA’s rover looks for life-friendly environments
2012 SCIENCE NEWS TOP 25: 2
Besieged by budget cuts and diminished by the end of the shuttle era, NASA got a welcome shot in the arm in August as mission controllers at the Jet Propulsion Laboratory in Pasadena, Calif., watched their latest interplanetary emissary guide itself to a safe landing on Mars. Curiosity’s arrival on the Red Planet ignited a firestorm of enthusiasm for space sciences, as millions followed the spectacular touchdown online.
The rover’s landing included a hypersonic parachute ride, then an acrobatic sky-crane maneuver involving a retro-rocket-powered descent stage that lowered the rover to the planet’s surface on nylon cables. Christened “Seven Minutes of Terror” by the JPL team, the rover’s entry, descent and landing were broadcast live over NASA’s TV network — and appeared on the big screen in New York City’s Times Square, where cheers erupted when the rover touched Martian soil around 1:30 a.m. on August 6 (SN: 8/25/12, p. 5).
Even the mission’s scientists and engineers began to attract rock star–like followings. There was “Elvis Guy” — entry, descent and landing lead Adam Steltzner, sporting a shellacked, lofty coif — and “Mohawk Guy” Bobak Ferdowsi, who rocked a star-spangled ’do. In an on-air phone call to mission control, President Barack Obama praised the team for exemplifying the best of “American know-how and ingenuity,” and for reaching beyond Earth to explore the vast unknown.
Its harrowing journey completed, Curiosity is now well into its primary mission: to search for evidence of past, and perhaps present, life-friendly environments on Mars.
“What we’d like to do is to begin to characterize habitable environments,” says project scientist John Grotzinger of Caltech. That task includes looking for signs of organic carbon and an energy source that could have powered Martian microbes in the distant past. In September, the rover returned evidence that water once flowed on the surface of Gale Crater (SN Online: 9/27/12). And in its first complete soil analysis, Curiosity found organic compounds, though it’s not clear whether they originated on Mars or were carried there by the rover (SN Online: 12/3/12).
Now the rover is en route to a mountain in the middle of Gale Crater. Mount Sharp — also known as Aeolis Mons — is a 5.5-kilometer-high peak built from sediment deposited over billions of years. Eventually, Curiosity will climb the mountain and read the history recorded in its layers.
“The question about habitability goes just beyond the simple observation of water on Mars, to re-creating the environments in greater detail with an understanding of the chemistry that was going on at that time — to ask if this is the kind of place that microorganisms could’ve lived,” Grotzinger says.
An onboard instrument called ChemCam is analyzing the ingredients in rocks littering the Martian surface. These measurements should provide important clues about whether early Mars really was warm, wet and capable of hosting life, as scientists suspect.
Curiosity’s investigations are being watched by orbiting spacecraft, which returned images of the rover parachuting to the surface and of the landing site, showing the ejected back shell and retrorocket-scorched dust. The rover is also sending home postcards — some self-portraits, others capturing the strangely familiar and yet alien landscape in the crater.
But the best images may still be from the video captured by Curiosity during its dramatic descent. Starting with the spacecraft’s heat shield falling away, the video — shot by a camera on the rover’s belly — tracks the swinging, plunging descent until touchdown, an event marked by the welcome sight of swirling Martian sands.