From: LARRY KLAES (ljk4_at_msn.com)
Date: Wed Jun 18 2003 - 10:35:19 PDT
http://www.ajc.com/news/content/news/atlanta_world/0603/18gsuchile.html
Georgia State University has joined forces with seven other institutions to operate four telescopes in Chile at the Cerro Tololo Inter-American Observatory, a mecca for astronomy in the lofty foothills of the Andes.
The move assures the university of a place in one of modern astronomy's most compelling quests in the decades ahead -- the search for Earthlike planets around other stars.
As a major partner in the operation of four Cerro Tololo telescopes, which were on the verge of being mothballed for lack of funding, Georgia State astronomers and students will get 150 nights of telescope time a year at one of the best known observatories in the Southern Hemisphere.
"Georgia State now has a south campus," says GSU astronomer Todd Henry, who heads the university's participation in the consortium.
The Chilean connection is the latest sign that Atlanta's downtown university is carving out a niche for itself among the institutional stars of big-time astronomy. Cal Tech and Harvard it's not, but for a school that didn't even have an astronomy department until the early 1970s, its stature is growing.
"We're still a small science department in a school not known for the sciences," says Bill Nelson, chairman of the physics and astronomy department. "But astronomy is a pretty big chunk of our resources."
In astronomical circles, a university's reputation depends less on size than on achievement -- and that depends on having ready access to costly instruments in faraway places. That access is often determined by a willingness to build and operate the facilities its astronomers need.
One hint of the university's commitment is the recently completed $13.5 million state-of-the-art telescope array on California's historic Mount Wilson -- a 15-year project headed by GSU astronomer Hal McAlister.
Closer to home, the university also operates three telescopes at Hard Labor Creek State Park, about 50 miles east of downtown Atlanta.
But GSU's latest coup -- a $100,000-a-year share of the research consortium that will operate the cash-strapped National Science Foundation telescopes near La Serena, Chile -- moves the university into the thick of one of astronomy's hottest new fields of discovery.
'Blue marbles'
In the last several years, astronomers have detected more than 100 stars with planets. All of the planets, however, appear to be giant, gaseous, Jupiterlike planets that are unlikely to support any form of life.
So the search for "blue marbles," like Earth, is just beginning. A $1 billion NASA mission scheduled for 2009 is designed to study star systems more likely to harbor life -- small, relatively cool stars that are some of the solar system's nearest, yet least known, neighbors in space.
GSU's Henry is one of the mission's principal investigators, as well as a member of the Research Consortium on Nearby Stars, under which Georgia State, Yale University, Ohio State University, Northern Arizona State University, the American Museum of Natural History and others will operate the Cerro Tololo telescopes.
One of the first uses of the telescopes will be to help find promising stellar targets for orbiting NASA spacecraft -- stars within 30 light-years that are small enough and cool enough to harbor Earthlike planets.
"I grew up in the Star Trek generation, so it's second nature to think about finding life in outer space," said Henry. "I think that sometime in my lifetime, we may do that."
Merely discovering such a place -- beyond the limits of detection with current technology -- is likely to be a decades-long pursuit. But Henry is convinced that nearby space is the best place to look.
Earthlike planets and the water that is considered essential for life can exist only in the so-called "Goldilocks zone" around other stars -- orbits where a planet's surface is not too hot for the water to boil away, and not too cold for it to freeze.
Those conditions, it is widely assumed, most likely exist around stars like our own sun, or perhaps around an even smaller class of stars known as "red dwarfs."
Hard to find red dwarfs
Finding red dwarfs isn't easy. Although they make up more than 70 percent of all stars in the universe, they burn so dimly they can't be seen with the naked eye.
Of the 200 billion stars in our own Milky Way galaxy, 140 billion are thought to be red dwarfs. There's a lot of room for future discoveries. Only 1 billion "known" stars are listed in the latest U.S. Naval Observatory catalog of the heavens.
Red dwarfs, in fact, are so faint that many of them, even those closest to home, in what Henry calls "the solar neighborhood," probably remain undiscovered.
The nearest star, Proxima Centauri, is a red dwarf. At a distance of only 4.2 light-years (about 25 trillion miles) it's a stellar stone's throw away.
This year, astronomers discovered a new star, a red dwarf that is 300,000 times fainter than the sun, reportedly a mere eight light-years away.
Of the 250 closest known star systems, Henry has discovered 13. The prospect of finding more of these glowing stellar embers is what draws Georgia State astronomers to the white-domed telescopes on the 7,000-feet summit of Cerro Tololo -- whose name in the language of the Aymara Indians means "edge of the abyss."
Cerro Tololo was chosen as a telescope site in 1963 to try to bring southern skies into focus with the sophisticated kind of telescopes which, until then, had been concentrated in the Northern Hemisphere. In the last 40 years, a half-dozen other telescopes -- including the four 8-meter telescope array of the European Southern Observatory Very Large Telescope -- have sprung up in the region as well.
The Cerro Tololo telescopes aren't nearly as powerful as are the "big glass" of the world's newest observatories. But competition for time on the bigger, newer telescopes doesn't allow the repetitive observations -- two years' worth or more -- needed to pinpoint locations of cosmic objects.
Red dwarfs aren't the only thing that Georgia State astronomers will be peering at from the mountaintop in Chile.
GSU astronomer Dick Miller will be using them to study active galactic nuclei and the behavior of black holes. Astronomer Doug Gies will be looking at active double stars in galactic clusters.
Even some of the university's 21 astronomy graduate students, like doctoral candidate Virginia McSwain, will be able to spend a week or two at the site while they work on their research projects. McSwain's interests run to micro-quasars, jets of luminous matter extending from the core of massive star systems.
"Having access to Cerro Tololo is a wonderful opportunity for all Georgia State students," McSwain says. "To be a professional astronomer, you need experience -- and the best way to get that is telescope time."
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