"It is a very sensitive sensing technique that can measure organic small molecules like carbon dioxide, lipids, and different fragmentations that makes it a very good biomarker detector," says Bin Chen, a senior scientist at NASA Ames Research Center (ARC), who's leading the development of the spectrometer.

The NASA scientists are working to increase the sensitivity of the spectrometer even further by coating the probe--a fiber bundle that the light goes through to illuminate the target and that also receives the signal bouncing back--in gold and silver nanomaterials. This will enhance the electromagnetic and plasmonic properties of the probe on a device, says Chen. NASA scientists had originally planned to deploy a form of the Raman spectrometer on Spirit, the Mars rover, but because they worried about the durability of the device, they removed the spectrometer at the last minute.

The scientists working on endurance are planning to meet in Mexico in a month to further discuss the technological reconstructions of depthx with lead engineer William Stone, of Stone Aerospace. They will be addressing how to make it smaller and more power-efficient, as well as how to increase the durability of the sensors so that they can withstand the temperatures of the arctic waters. Once depthx is reconstructed, the scientists plan to do a small test of the device in an ice-bound lake in Wisconsin next spring before deploying the robotic probe to the Antarctic waters in November 2008. There the device will be tested for a month; scientists will be spending eight hours a day taking measurements.

"Determining the biogeography of the Antarctica lake could be a model for life on early Mars, so if you imagine how life survived on Mars, like, three billion years ago, it may be like the dry valley of lakes in Antarctica," says Chris McKay, a planetary scientist at NASA and a project coinvestigator. Mapping an ecosystem under the lake will help scientists better understand how life might be able to survive on ice-covered oceans on moons such as Jupiter's Europa.