Monday saw the news that a scoop soil of Mars analyzed by scientists contained water and a mix of chemicals, but not complex carbon-based molecules considered essential for life.
The find did not surprise planetary scientist Paul Mahaffy since radiation from space can destroy any carbon evidence.
“It’s not unexpected necessarily,” said the scientist of NASA’s Goddard Space Flight Center, who is in charge of the chemistry experiments. “It’s been exposed to the harsh Martian environment.”
“Just finding carbon somewhere doesn’t mean that it has anything to do with life, or the finding of a habitable environment,” lead scientist John Grotzinger of the California Institute of Technology told reporters at the American Geophysical Union conference in San Francisco.
“If you have organic carbon and you don’t have any water, you don’t have a habitable environment,” he added.
As Reuters explains, even with carbon and water, for an alive creature other chemicals are required, such as sulfur, oxygen, phosphorous and nitrogen, to form and evolve.
“It’s not unexpected that this sand pile would not be rich in organics. It’s been exposed to the harsh Martian environment,” added mission scientist Mahaffy.
“It’s really going to be an exciting hunt over the course of this mission to find early environments that might be protected from this surface Mars environment and see what we can add to the carbon story,” the scientist said.
Scientists do not know if the carbon compounds in the soil are contamination from Earth, arrived on the surface of Mars via comets or asteroids, or, if they are indigenous, whether they came from geological or biological activities on Mars.
“It tells us that we have a lead into a measurement of one of the important ingredients that adds to a habitable environment,” Grotzinger said. “We still have a lot of work to do to qualify and characterize what it is.”
The rover is expected to reach a richer slice of Martian history next year when it begins examining layers of sediment in a mountain rising from the floor of the crater.
“We’re starting to find the spices that make a stew tasty. There are the basic ingredients that you expect to be there, but it’s how you combine them and the minor ingredients that really turn out to be interesting,” he said.
“What this mission is about is integrated science,” Grotzinger added. “There is not going to be one single moment where we all stand up and on the basis of a single measurement have a hallelujah moment.”
Data collected during the rover’s four-month mission indicates that astronauts are likely to face almost the same dosages of radiation as they do aboard the International Space Station. However, that amount likely will increase as the sun moves into the more active phase of its 11-year cycle.
Moreover, astronauts would surpass career radiation limits imposed by the agency if the higher radiation level experienced during the nine-month cruise to the Red Planet were taken into account, claim scientists.
“We can survive the Mars surface. The hard part is the cruise,” said Donald Hassler, with the Southwest Research Institute in Boulder, Colorado.
NASA is currently working on spacecraft shielding and protocols in order to counter the effects of solar and cosmic radiation.