• E-mail
• Print
• Comment
• Font Size
• Digg
• del.icio.us
• Discuss article

Astronomy's Own Star Speaks at Gtcc ; R. Paul Butler, an Internationally Known Planet Hunter, Visits the School's Jamestown Campus Tonight.

Posted on: Saturday, 18 September 2004, 06:00 CDT

There are planets orbiting stars trillions of miles away.

We can't see them. But they're there.

Tonight, you can meet the man who will explain how we know they're there.

R. Paul Butler, of the department of terrestrial magnetism at the Carnegie Institution of Washington, will speak at GTCC at 7:30.

Butler and Geoffrey Marcy of the University of California at Berkeley lead the team that has found most of 135 known extrasolar planets, those outside the Earth's solar system.

The session is just one of four sponsored across the nation each year by the American Astronomical Society's second century lecture series.

Tom English, GTCC professor of astronomy, likens Butler's visit to that of a rock star.

"For centuries we've been wondering, 'Are we alone?"' English said. "We have all sorts of science-fiction TV that plays to that, but prior to the 1990s there was no direct evidence" of planets outside our solar system.

In fact, at the height of the Inquisition in Europe, scholars were burned at the stake for even suggesting the existence of other systems.

Butler, English said, helped to bring the planets out of the dark by developing a system that uses the Doppler effect to detect the presence of planets circling stars.

The planets cannot be seen through a telescope, English said. The closest star that a planet has been found circling is roughly 4.2 light-years away. A light-year is equal to nearly

6 trillion miles.

"If you're looking at stars that are 100 trillion miles away and a little tiny planet going around real close, it's like trying to see a mosquito flying around the field lights at the stadium in Charlotte, from here."

To "see" the planet, astronomers use the light emitted by the star. Butler's team found that when applying the Doppler effect to the spectrum of light the star is emitting, the star seems to "wobble" back and forth slightly.

The wobble is actually caused by the planet orbiting the star and tugging on it as it moves around. The movement is not large, but it is enough to be detected in the light coming from the star.

"There's a lot of computer analysis. It's pretty complicated," English said of the planet hunt.

During his speech tonight, Butler is expected to discuss the discoveries, including that of several planets the size of Neptune in the past few weeks, as well as future developments in the field.

Although Butler can prove the planets are out there, no one has found extraterrestrial life yet, English said.

The solar systems Butler's team has discovered have large planets, orbiting very close to their suns, making for harsh environments that are bombarded by killer light rays and scorching heat.

"The way you kill life in the lab is to bombard it with X-rays, and that's the exact environment that exists there," English said. "It wasn't a real hopeful development (for life).

"What's funny is that none of these other solar systems look like ours," he said. "Maybe we're abnormal."

Contact Allison Perkins at 373-7157 or aperkins@news-record.com YES

More News in this Category