Searching for Life on Mars

More than two years after its precisely calibrated landing on the floor of a Martian crater in August 2012, NASA’s one ton, SUV-sized Curiosity rover has traveled more than five miles across the rocky, massive Gale crater to the base of an 18,000-foot mountain, Mount Sharp. The rover is the crowning achievement of the Mars Science Laboratory, a NASA mission managed by the Jet Propulsion Laboratory in Pasadena, California.

Nathalie Cabrol, a planetary scientist at the NASA Ames Research Center in Mountain View, California, called Curiosity “the Swiss Army knife” of Mars rovers. It’s an apt metaphor, considering that Curiosity is the most advanced scientific laboratory ever deployed on the Red Planet. Its suite of 11 scientific instruments, including cameras that are capable of capturing stunning high-definition photos of the Martian landscape,  have already yielded more data than all previous Mars rover missions combined.

One of Curiosity’s biggest findings so far was announced last year, when scientists unveiled images taken by the rover of an ancient streambed, where gravelly rocks provided proof that water once flowed on Mars and could have actually supported life millions or billions of years ago.

Curiosity continues to make sophisticated measurements of the geological and chemical composition of Mars. In late September 2014, Curiosity drilled into the base of Mount Sharp and analyzed the sample to unearth clues about how the towering peak formed in the center of Gale crater.

After Curiosity drills into Martian rock, it probes the powdery sample with an x-ray beam. The diffraction or scattering of the x-rays reveal the sample’s structure and composition. The data is then relayed to an orbiting satellite and eventually reaches a team of NASA scientists who meticulously comb through the rover’s measurements and observations. Already, Curiosity’s data has revealed the presence of oxygen, water, carbon and sulfides – elements that are necessary to support life.

Although Curiosity cannot detect signs of current life on Mars, astrobiologists such as Christopher McKay of NASA Ames Research Center say they are excited to see Curiosity’s observations which are painting a fuller, more complex picture of the habitability of our closest planetary neighbor.

“Mars is really interesting for the search for life, because it’s a world which we know at one time had an Earth-like period,” McKay said, adding that if there was life on Mars it could have represented “a separate origin of life, a second Genesis” that was different from the evolution of life on Earth.

Meanwhile, an international race to explore Mars is heating up, with news in September 2014 that the Indian Space Research Organization had succeeded – on its first attempt – in launching a spacecraft into the orbit of Mars where it began mapping the Martian surface. NASA has already announced  a new mission, Mars 2020, with a successor to the Curiosity rover that will have several goals, including testing new technology to pave the way for a human mission to Mars.

For decades, Hollywood has offered up fanciful, even absurd sci-fi scenarios of what a human mission to Mars would look like, often with catastrophic results for the astronauts. But now, the road to a human exploration of Mars finally looks real, paved by the observations and measurements of dutiful robotic rovers blazing new trails of scientific discovery and wonder.

This video story was originally produced by Rachel Silverman and updated by Sheraz Sadiq. 

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