The goal of NASA's Curiosity rover is to determine if Mars was ever capable of supporting life. But the Agency's next rover, set to launch in 2020, could take things one giant step further. Given recent findings, says Jack Mustard, chairman of the Agency's Science Definition Team, "past Martian life seems possible, and we should begin the difficult endeavor of seeking the signs of life."
In an announcement issued yesterday by NASA, Mustard was quick to point out that "the Mars 2020 mission concept does not presume that life ever existed on Mars," only that searching for signs of past life – microbial life, specifically – is the next logical step for future robotic investigations of the Red Planet. Withholding presumption is, of course, is good science. Besides, Mustard says, "no matter what we learn, we would make significant progress in understanding the circumstances of early life existing on Earth and the possibilities of extraterrestrial life."
If NASA accepts the suggestion of Mustard and his Science Definition Team – which comprises a group of 19 scientists and engineers, representing a range of universities and research organizations – it will use the team's input to form the basis of the rover's mission objectives. Those objectives will, in turn, be used to solicit input on what instruments should be included in the rover's scientific payload. The current plan is to outfit a rover similar to Curiosity, allowing NASA to rely on field-tested engineering specifications, launch protocols and procedures for atmospheric entry, descent and landing on Mars. These are all excellent ideas, in that they allow NASA to minimize production costs while maximizing the odds of getting the rover to the planet's surface safely.
"Where Curiosity takes rocks and grinds them up into powder and looks at their bulk constituents, what this mission would need to do is be able to look at a microscopic level," says Lindy Elinks-Tanton, Science Definition team member and director of the Carnegie Institution for Science's Department of Terrestrial Magnetism, in the overview video featured above. She says the rover would then "examine the rocks for these very tiny and detailed messages that they would be sending to us about the past life that could have lived there."
NASA claims it will conduct an open competition to determine what instruments, specifically, will be included on the rover. A search for traces of microbial life would of course necessitate the use of optical instruments with microscopic resolutions. Conveniently, the Agency notes that the same measurements used to scan for traces of ancient life could also be used to select samples that could return to Earth in a later mission. Consequently, Mustard's team has proposed the rover collect and store as many as 31 rock core and soil samples that might later be returned to Earth for more rigorous analysis.
Above: A prototype for hardware to cache samples of cores drilled from Martian rocks for possible future return to Earth. For scale, the diameter of the core sample shown in the image is one centimeter | Image Credit: NASA/JPL-Caltech
"No matter how well instrumented a rover is, we can't look with the kind of detailed understanding that we would have with laboratories back here on Earth," explains Elinks-Tanton, alluding to future missions that could see cores from the storage cache returned to Earth for in-depth analysis. Planetary Scientist Jim Bell, another member of Mustard's team, echoes her sentiments:
"We can do so much more in the laboratory on the Earth, with equipment that exists now. And who knows what's going to be invented in the decades ahead that can still analyze those rocks?"
Whether the rover is analyzing soil and core samples right on Mars, or storing them for a future return trip to Earth, a Mars rove designed to look for life, specifically, would represent a monumental step forward for the Agency, not just scientifically, but ideologically and philosophically, as well.
"The Mars 2020 mission will provide a unique capability to address the major questions of habitability and life in the solar system," said Jim Green, director of NASA's Planetary Science Division in Washington. "This mission represents a major step towards creating high-value sampling and interrogation methods, as part of a broader strategy for sample returns by planetary missions."
For more informaiton, visit NASA JPL.