Decision-making software on NASA's Earth Observing-1 spacecraft is wading through copious amounts of data to determine which information should be downloaded and studied first, saving researchers at Goddard Space Flight Center in Greenbelt, Md., both time and money.

The program, known as Autonomous Sciencecraft software, looks at very specific elements tracked by EO-1, such as volcanic eruptions, and then uses algorithms to "decide" without the intervention of someone on the ground to monitor the specific area of an eruption and automatically send that data to Earth within the hour, said Steve Chien, a principal investigator at NASA's Jet Propulsion Laboratory in Pasadena, Calif., who spoke at the American Geophysical Union's joint assembly here May 25.

EO-1 is designed to test imaging technology and collect large amounts of data, so much that not all of it needs to be downlinked to Earth, Chien said.

"It can decide on its own based on priorities programmed into it, to re-image targets and almost immediately begin reprogramming," Chien said.

The software has been used on EO-1 for a little more than a year, and also has provided more accurate data for flood monitoring, and for looking at freezing and thawing patterns, Chien said.

Now that the software is in use, scientists are 100 times more likely to receive data that actually has valuable information for the study of these particular changes, Chien said.

Another benefit, Chien said, is that mission costs have been reduced from $3.6 million per year to $1.6 million per year, since the software was implemented.

Chien said these cost savings likely drove the mission's extension to October of 2007.

Rebecca Castano, a principle investigator of the Onboard Autonomous Science Investigation System, also at the Jet Propulsion Laboratory, is hoping similar software will help filter all the data currently being collected by the Mars rovers and Mars Odyssey missions. On Mars Odyssey, the software will home in on thermal anomalies, as well as water ice clouds, and dust storms when they are just being initiated, Castano said at the joint assembly.

Castano said dust devils and clouds are rare events, and very seasonal, and having software that can home in on target areas is more efficient than constantly observing the areas and bringing back a lot of useless data, Castano explained.

The algorithms for the Mars missions are ready to be uploaded sometime during early summer in 2006, Castano said.

For the rover's ChemCam instrument, which attempts to find rocks worthy of study, the software has the potential to dramatically increase the likelihood of the rover finding a rock rather than just soil, Castano said, noting that the rovers are only successful at finding an actual rock about 10 percent of the time. With the new software she is hopeful that will grow to a 90-percent success rate.

Ralph Lorenz, an assistant research scientist at the Lunar and Planetary Laboratory at the University of Arizona in Tucson, said this type of software could be instrumental in studying Saturn's moon Titan in the future with an airborne platform.

Lorenz said that if such a mission is green-lighted, Titan's varied surface environment, which contains crusts of ice and sand dunes, would be much easier to study because the moon is so far away from the Earth, making communications with an aircraft extremely difficult.

Autonomous software, Lorenz said, could help position whatever aircraft would be used, such as some sort of hot air balloon-type device, in an area likely to produce profitable samples.