Waggoner and his colleagues have designed a life detection system equipped to detect fluorescence signals from sparse life forms, including those that are mere millimeters in size. Their fluorescence imager, which is located underneath the rover, detects signals from chlorophyll-based life, such as cyanobacteria in lichens, and fluorescent signals from a set of dyes designed to light up only when they bind to one of the following ?nucleic acid, protein, lipid or carbohydrate ?all molecules of life.
"We don't know of other remote methods capable both of detecting low levels of micro-organisms and visualizing high levels incorporated as biofilms or colonies," said Gregory Fisher, project imaging scientist.
"Our fluorescent imager is the first such system to work in the daylight while in the shade of the rover. The rover uses solar energy to operate so it needs to travel during daylight hours. Many times, the images we capture may only reveal a faint signal. Any sunlight that leaks in to the camera of a conventional fluorescence imager would obscure the signal," said Waggoner.
"To avoid this problem, we designed our system to excite dyes with high intensity flashes of light. The camera only opens during those flashes, so we are able to capture a strong fluorescence signal during daytime exploration," said Shmuel Weinstein, project manager.
During the mission, a remote science team located in Pittsburgh instructed the rover's operations. A ground truth team at the site collected samples studied by the rover to bring back for further examination in the lab. On a typical day in the field, the rover woke up and followed a path designated the previous day by the remote operations science team. The rover followed a transect and stopped o
Source:Carnegie Mellon University