NASA device to accelerate search for alien life

Jennifer Holmes Arizona Daily Wildcat Astronomer for Steward Observatory, Neville Woolf lectures on the possible existence of life on other planets. For 70 years Steward Observatory has given free lectures and public viewings on the observatory's telescope.

In 1995, the National Aeronautics and Space Administration began developing a plan called Terrestrial Planet Finder to search for signs of life on distant, undiscovered planets.

The project, to be implemented around 2015, would survey nearby stars to find planets hidden by solar glare.

Dr. Neville Woolf, a University of Arizona astronomy professor, said a new project known as the Planet Detection Interferometer could help narrow the field of potential solar systems to facilitate the search for extraterrestrial life.

The method would allow scientists to find planets as soon as 2005, although it would not have the Terrestrial Planet Finder's ability to search for an atmosphere and signs of life on the planets until 10 years later, he said.

Woolf presented a lecture titled "An Earlier Look at Earth-Like Planets" last night at the UA's Steward Observatory as part of a bi-monthly speaker series.

"The advantage (of the interferometer) is you can send up something faster to learn about the present," he said. "If we can find out where the Earth-like planets are, then we can plan to study them in the most efficient way."

The interferometer method uses four telescopes, each a meter in diameter, that individually detect the planetary system as a single fuzzy patch.

When used together, the telescopes eliminate the glow from starlight that prevents planets from being seen. The planet-finding system would be launched into space when development is completed.

Scientists have seen how the gravity of undiscovered planets has on the motions of stars, but have not actually seen the planets themselves.

"It's a great idea," Woolf said of the new project.

He said once a planet is identified, scientists can run more sophisticated tests to determine its ability to sustain life.

"If you find a planet with a lot of ozone in the atmosphere," Woolf said, "you have almost certainly found a planet with life on it."

Woolf said one problem is that dust in the solar system and the Earth's heat severely limit the interferometer's use. Therefore, more research is needed.

"The technique does work," Woolf said. "Unfortunately it doesn't work well enough yet."

Stephanie Corns can be reached via e-mail at Stephanie.Corns@wildcat.arizona.edu.