Is There Life on Mars? Lidar Device May Be Able to Tell Us.

A biosensor currently used by the U.S. military to remotely monitor the atmosphere for potential toxins has inspired a novel device that could be used for detecting biosignatures in space.

The Bio-Indicator Lidar Instrument, or BILI, is a prototype of a fluorescence-based lidar that may ultimately be used in space exploration to analyze particles for organic material. Positioned on the mast of a planetary rover, BILI would scan the terrain looking for dust plumes. Once a plume was detected, pulsed light from two UV lasers would be directed at it, causing the particles inside the plume to resonate or fluoresce. By analyzing the fluorescence, scientists could determine if the dust contained organic particles created relatively recently or in the past. The analysis also could reveal particle size.

An artist’s rendition showing how a proposed laser-fluorescence instrument could operate on Mars. Courtesy of NASA.

"If the biosignatures are there, it could be detected in the dust," said NASA Goddard technologist Branimir Blagojevic.

BILI, which has the ability to detect in real-time small levels of complex organic materials from a distance of several hundred meters, could autonomously search for biosignatures in plumes above recurring slopes and other areas not easily traversed by a rover. Further, BILI could perform a ground-level aerosol analysis from a distance, reducing the risk of sample contamination.

"This makes our instrument an excellent complementary organic-detection instrument, which we could use in tandem with more sensitive, point sensor-type mass spectrometers that can only measure a small amount of material at once," Blagojevic said. "BILI's measurements do not require consumables other than electrical power and can be conducted quickly over a broad area. This is a survey instrument, with a nose for certain molecules."

Branimir Blagojevic has developed a prototype instrument that would 'sniff' for biosignatures in Martian dust. The screen behind Blagovevic shows the graphics user interface for the Bio-Indicator Lidar Instrument, developed by Science and Engineering Services, Inc. while he worked there. Courtesy of NASA/W. Hrybyk.

With such a tool, which also could be installed on an orbiting spacecraft, NASA could dramatically increase the probability of finding biosignatures in the solar system, he added.

"We are ready to integrate and test this novel instrument, which would be capable of detecting a number of organic biosignatures," Blagojevic said. "Our goal is increasing the likelihood of their discovery."

Blagojevic hopes to further advance BILI by ruggedizing the design, reducing its size, and confirming that it can detect tiny concentrations of a broad range of organic molecules, particularly in aerosols that would be found at the ground level on Mars.

Blagojevic formerly worked for a company that developed the sensor used by the military. By developing BILI, he has shown that the same remote-sensing technology used to identify biohazards in public places could be effective at detecting organic biosignatures on Mars and other targets in the solar system.

"This sensing technique is a product of two decades of research," he said.