In findings that are as scientifically significant as they are crushing to the popular imagination, NASA reported Thursday that its Mars rover, Curiosity, which has been trundling across the red planet for a little over a year, has deflated hopes that life could be thriving on Mars today.
The conclusion, published in the journal Science, comes from the fact that Curiosity has been looking for methane, a gas that is considered a possible calling card of microbes, and has so far found none of it. While the absence of methane does not entirely preclude the possibility of present-day life on Mars, it does return the idea to the realm of pure speculation without any hopeful data to back it up.
“You don’t have direct evidence that there is microbial process going on,” as Sushil K. Atreya, a professor of atmospheric and space science at the University of Michigan and a member of the science team, put it.
The history of human fascination with the possibility of life on Mars is rich, encompassing myriad works of science fiction, Percival Lowell’s quixotic efforts to map what turned out to be imaginary canals, Orson Welles’ panic-inducing 1938 “Attack by Mars” radio play, and of course Bugs Bunny’s nemesis Marvin the Martian.
But NASA scientists are going strictly by their data, and they are having none of it. Asked the same question once posed by David Bowie — “Is there life on Mars?” — John Grotzinger, the project scientist for the Curiosity mission, would only go so far as to say that the lack of methane “discounts” the possibility of living creatures going about their business on Mars.
“It does diminish the argument that there are methanogenic organisms there,” Dr. Grotzinger said.
A decade ago, observations from telescopes on Earth and a spacecraft orbiting Mars suggested that vast plumes of methane were rising from certain regions, but Curiosity’s readings now bring the earlier claims into question.
“It just isn’t there,” said Dr. Atreya, referring to methane.”
– The New York Times, "Mars Rover Comes Up Empty In Search for Methane"
DICKS IN SPACE No, the NASA rover Curiosity did not draw a penis on the surface of Mars. However, Curiosity'smission controllers should probably refrain from having the probe make K-turns from now on, lest they elicit giggles from the same group of little boys who think the Valles Marineris looks like a vagina. (Via the Herald Sun)
PROBE-LEM A self-taken photomosaic of the rover Curiosity taken in February. The NASA probe had been all but shut down for the past three weeks as engineers with the space agency figured out what caused both onboard computers to shut down. Off the record: the Klingons did it. (Photo: NASA via Reuters / The New York Times)
A panoramic view of the NASA rover Curiosity, stitched together from several self-portrait shots taken in the Yellowknife Bay section of the Gale Crater on Mars. Click through for larger… and lonelier. (via NASA APOD)
NOT BRUNO MARS NASA’s Mars rover Curiosity is pictured in this self-portrait, stitched together from dozens of photos taken by the rover’s Mars Hand Lens Imager (MAHLI). Curiosity is atop a flat outcrop called John Klein, which will serve as the first site for the rover’s rock-drilling activities. (Photo: NASA via The Telegraph)
SEA OF TRANQUILITY A panoramic image of Point Lake on Mars, taken by the NASA rover Curiosity in November. (via NASA APOD)
Unexpected mineral finds prompt scientists to decide to drill.
Delighted members of the Curiosity science team announced Tuesday that the rover was now in a virtual “candy store” of scientific targets—the lowest point of Gale Crater, called Yellowknife Bay, is filled with many different materials that could have been created only in the presence of water. (Related:“Mars Has ‘Oceans’ of Water Inside?”)
Project scientist John Grotzinger, of the California Institute of Technology in Pasadena, said during a press conference that the drill area has turned out “to be jackpot unit. Every place we drive exposes fractures and vein fills.”
Mission scientists initially decided to visit the depression, a third of a mile from Curiosity’s landing site, on a brief detour before heading to the large mountain at the middle of Gale Crater. But because of the richness of their recent finds, Grotzinger said it may be some months before they begin their trek to Mount Sharp.
The drilling, expected to start this month, will dig five holes about two inches (five centimeters) into bedrock the size of a throw rug and then feed the powder created to the rover’s two chemistry labs for analysis.
A Watery Past?
That now desiccated Mars once had a significant amount of surface water is now generally accepted, but every new discovery of when and where water was present is considered highly significant. The presence of surface water in its many possible forms—as a running stream, as a still lake, as ground water soaked into the Martian soil—all add to an increased possibility that the planet was once habitable. (Watch a video about searching for life on Mars.)
And each piece of evidence supporting the presence of water brings the Curiosity mission closer to its formal goal—which is to determine whether Mars was once capable of supporting life.
Curiosity scientists have already concluded that a briskly moving river or stream once flowed near the Gale landing site.
The discovery of the mineral-filled veins within Yellowknife Bay rock fractures adds to the picture because those minerals can be deposited only in watery, underground conditions.
"You gypsum, you lose some."
— Curiosity mission controller
LOOKER A mosaic of images from the Curiosity rover’s Mars Hand Lens Imager on Oct. 31 shows the rover’s camera mast and deck. The pictures were taken during operations at a Martian sampling site known as Rocknest. (Photo: NASA / CalTech / JPL via NBC News)
TOKEN / TAKEN A photo of the calibration target for the Mars Hand Lens Imager (MAHLI) aboard NASA’s Mars rover Curiosity, taken by that camera on Mars. The calibration target includes colour references, a metric bar graphic, a 1909 VDB Lincoln penny, and a stair-step pattern for depth calibration. The penny is a nod to geologists’ tradition of placing a coin or other object of known scale as a size reference in close-up photographs of rocks. (NASA via The Telegraph)
I LOOK GOOD A mosaic of photos taken by an imager on NASA’s Curiosity rover shows the underside of the rover and its six wheels, with Martian terrain stretching back to the horizon. The four circular features on the front edge of the rover are the lenses for the left and right sets of Curiosity’s hazard avoidance cameras, or Hazcams. Because of the different perspectives used for different images, some of the borders of the photos don’t line up precisely. (Photo: ASA / JPL via NBC News)
ROAD TRIP Tracks from the first drives of NASA’s Curiosity rover are visible in this image captured by the High-Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter. (Photo: NASA-JPL via The Telegraph)
NASA’s Mars rover Curiosity has beamed home the first human voice ever sent from another planet, as well as some spectacular new images of its Martian environs.
The 1-ton Curiosity rover broadcast a greeting from NASA administrator Charlie Bolden, who congratulated the mission team for getting the huge robot to Mars safely. While the significance of the audio accomplishment is largely symbolic, NASA officials hope it presages a more substantial human presence on the Red Planet down the road.
“With this, we have another small step that’s being taken in extending the human presence beyond Earth, and actually bringing that experience of exploring the planets back a little closer to all of us,” said Curiosity program executive Dave Lavery, invoking the famous line late astronaut Neil Armstrong uttered from the surface of the moon on July 20, 1969.