Spacecraft That Think
There's nothing worse than a satellite that can't make decisions. Rather than organizing data, it simply spews out everything it collects, swamping scientists with huge amounts of information. It's like getting a newspaper with no headlines or section pages in which all the stories are strung together end-to-end.

Researchers at the University of Arizona (UA), Arizona State University (ASU) and the Jet Propulsion Laboratory (JPL) are working to solve this problem by developing machine-learning and pattern-recognition software. This smart software can be used on all kinds of spacecraft, including orbiters, landers and rovers.

Scientists currently are developing this kind of software for NASA's EO-1 satellite. The smart software allows the satellite to organize data so it sends back the most timely news first, while holding back less-timely data for later transmission. Although the project, called the Autonomous Sciencecraft Experiment (ASE), is still in the test and development stage, software created by UA hydrologists has already detected flooding on Australia's Diamantina River. "We had ordered some images from the satellite to test our software in the lab," said Felipe Ip, a doctoral student in UA's Hydrology and Water Resources (HWR) Department. "We didn't know the Diamantina River was flooding, but when we started running the images through our software, it told us, ‘Hey, we've got a flood here.' We were delighted because that's just what it's supposed to do."

While Ip, under the direction of HWR researchers James Dohm and Victor Baker, is developing the flood-detection software for EO-1, JPL team members are creating similar software to detect volcanic activity and ASU researchers are working on software to find changes in ice fields

Saturn's Phoebe: Kin to Comets?
Scientists may at last have settled the debate on the origin of Saturn's moon, Phoebe. They analyzed results from the Cassini Visual and Infrared Mapping Spectometer (VIMS) taken during the June 11 Cassini spacecraft's Phoebe flyby.

Scientists have long doubted that Phoebe, captured in orbit when it wandered in from the Kuiper belt, the frigid region beyond the orbit of Neptune, came from the same disk of material that formed Saturn and most of its moons. Phoebe revolves backward with respect to both Saturn's rotation and orbital motion, and travels in the opposite direction of Saturn's other satellites.

Phoebe is widely believed to have wandered past Saturn and been captured by that planet's mighty gravitational field. Where it wandered from was the question.

It is clear that the materials in Phoebe's surface bear little resemblance to the predominantly rocky material found in asteroids in the belt between Mars and Jupiter. The materials that make up Phoebe formed farther out in the solar system, where it is cold enough for them to remain stable.

"One intriguing result of the VIMS measurements is the discovery of possible chemical similarities between the materials on Phoebe and those seen on comets," said VIMS team leader Robert H. Brown of the University of Arizona.

Parting Genomes: UA Biologists Discover Seeds of Speciation
The first eyewitness to the birth of a new species may be a University of Arizona graduate student. Her new findings could help biologists identify and understand the precise genetic changes that lead one species to evolve into two separate species.

Graduate student Laura K. Reed and her adviser Therese Markow, a UA Regents' Professor, may have discovered the birth of a new species by observing breeding patterns of fruit flies that live on rotting cacti in western deserts. Whether the closely related fruit fly populations, designated Drosophila mojavensis and Drosophila arizonae, represent one species or two is still debated by biologists, testament to the UA researchers' assertion that the insects are in the early stages of diverging into separate species. While the evolutionary record is brimming with examples of speciation events, biologists haven't been able to put their fingers on just what initiates the reproductive isolation, Reed said. Several researchers have identified mutant forms of certain genes associated with the inability of fruit flies to hybridize with closely related species, but those were discovered long after the two species diverged. Reed said the researchers need to catch the genetic schism while it's still brewing. Now she and her adviser have managed to do just that. In the wild, the two fruit flies Drosophila mojavensis and Drosophila arizonae rarely, if ever, interbreed, even though their ranges overlap in a broad swath along the northern Mexican coastline. In the lab, researchers can coax successful conjugal visits between members of the two groups. But even under laboratory conditions such matings aren't always fruitful. Drosophila mojavensis mothers typically produce healthy offspring after mating with Drosophila arizonae males, but when Drosophila arizonae females mate with Drosphila mojavensis males, the resulting sons are sterile. Reed said such limited capacity for interbreeding suggests the two groups of flies are on the verge of becoming completely separate species.