Tool makes search for Martian life easier

Finding life on Mars could get easier with a creative adaption to a common analytical tool that can be installed directly on the robotic arm of a space rover.

In a recent paper published online in the journal Planetary and Space Science, a team of researchers propose adding a laser and an ion funnel to a widely used scientific instrument, the mass spectrometer, to analyze the surfaces of rocks and other samples directly on Mars' surface. The researchers demonstrated that the combined system could work on the spot, without the sample handling that mass spectrometry usually requires.

"There are a lot of exciting discoveries about Mars that have yet to be made," said the paper's lead author, Paul Johnson. "This technique could make understanding the composition of rocks and soils on Mars - possibly including evidence of life - much easier."

Johnson, of NASA's Jet Propulsion Laboratory in Pasadena, Calif., came up with the idea after reading about an ion funnel technology for mass spectrometry developed by Keqi Tang and Dick Smith of the Department of Energy's Pacific Northwest National Laboratory. William Brinckerhoff of NASA's Goddard Space Flight Center in Greenbelt, Md., contributed his expertise in miniaturizing scientific instruments to the project, while Robert Hodyss, also of JPL, provided hands-on expertise during experimentation and testing.

Here on Earth, mass spectrometry is a common analytical technique scientists use to identify molecules, their elements and their isotopes in samples ranging from rocks to proteins. It works by turning a sample's molecules into electrically charged ions. A mass spectrometer then precisely measures the mass of ions and ion fragments to identify the sample's contents at a detailed molecular level.

Mass spectrometry isn't new to space exploration. It was used to analyze Martian soil for the first time as part of NASA's Viking program in the 1970s. And it's planned to be part of the Mars Science Laboratory's Curiosity rover, which will lift off for the Red Planet this November. But each time it's been used in space, the samples had to be extensively prepared before they could be analyzed.