PNNL develops technology for space rover

RICHLAND — Technology developed at Pacific Northwest National Laboratory in Richland could one day land on Mars to help in the search for signs of life there.

NASA's Jet Propulsion Laboratory is proposing adding the technology, an ion funnel, plus a laser to a mass spectrometer that would be carried on a robotic arm of a space rover.

The combined system could work on the spot, without the sample handling that mass spectrometry usually requires, according to a paper published in the journal Planetary and Space Science by researchers from the Jet Propulsion Laboratory, the national lab in Richland and NASA.

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

Johnson came up with the idea for the system after reading about the ion funnel technology for mass spectrometry developed by Keqi Tang and Dick Smith at PNNL, which is a Department of Energy research lab.

Mass spectrometers work by turning a sample's molecules into electrically charged ions and then measuring the mass of those ions to identify the sample's contents at a molecular level.

But when using traditional methods, much of the sample being analyzed was lost as ions passed from regions of high pressure to reach lower pressure regions where the actual mass spectrometer can function.

To solve this problem, Smith and Tang developed an ion funnel that creates a repelling electric field, which focuses and transmits ions into the low-pressure chamber of the mass spectrometer with 100 percent efficiency.

"We didn't specifically design the ion funnel for space exploration, but we're excited that it and Mars are a good fit," Tang said in a statement.

Jet Propulsion Laboratory scientists also have added a laser to the proposed system to eliminate the need for soil and rocks to be scooped up, placed into a chamber and heated to convert the sample into a gas before it could be analyzed.

"Cutting rocks, picking them up and moving them around, all this adds complexity," Johnson said.

Instead, he's proposing shooting a laser at the sample's surface, which creates a plume of molecules and ions that can be analyzed by the mass spectrometer.

PNNL researchers have tested the proposed technology in a sealed chamber that matches Mars' atmospheric conditions, shooting laser pulses at samples of copper, stainless steel and gypsum.

It worked as hoped, peeling a layer of atoms off the surface of the samples and then transforming them into ions.

The ion funnel then was quickly pulled into the mass spectrometer for identification, according to the Jet Propulsion Laboratory.

The next step will be to make the system as small and light as possible so it can fit onto the robotic arm of a space exploration rover.

Annette Cary: 582-1533;