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Archer Points Way to Black Hole Hunting Grounds: ; Astronomers Use Infrared to Pick Through Galaxy Debris

Posted on: Tuesday, 20 July 2004, 06:00 CDT

MAUNA KEA, Hawaii - Steve Eikenberry hovers over the dashboard, squinting into the darkness, wishing he had remembered to bring a pair of gloves.

His windows are rolled up. His heater is on full bore. A frigid gale is scouring the rocky plateau at the top of this mountain. It buffets the sport utility vehicle as if to pluck it off the road and fling it into the void, a possibility that seems even likelier after Eikenberry flicks off his headlights and glides across the top of this 13,796-foot peak like a moviegoer creeping into a drive-in.

It does not feel like Hawaii. It feels like the end of the Earth.

Then, one by one, a dozen bulbous metal towers appear, illuminated by the amber glow of the parking lights. They are astronomical observatories, filled with instruments so delicate that headlights would have blinded them.

Eikenberry, 36, knows his way around this place. He is one of the rising stars of infrared astronomy - and part of a newly assembled team of researchers at the University of Florida that has turned what was once an obscure astronomy department into one of the best in the country.

Last year, Eikenberry tracked down and measured a fiery behemoth that turned out to be the most luminous star ever discovered.

Now he has come to Mauna Kea to study places that make its wild heights look tame.

Eikenberry's specialty, in the understated parlance of his trade, is the study of "compact objects." What that means is that he gets to sit in on some of the universe's most dramatic deathbed scenes.

Compact objects are dead or dying stars. Some are burned-out cinders so unimaginably dense that a teaspoon can weigh more than a city block. Some undergo such intense compression that they become one of the most fearsome forces in the cosmos: black holes.

Black holes are where matter meets energy and loses the battle once and for all. The core of a dead star has been crushed into subatomic puree and beyond, leaving behind only the colossal gravity generated by its own evaporated mass. Nothing in the universe can escape this force: not matter, not light, not even time and space.

Other stars caught in the gravity of black holes spiral slowly around them like water down the drain. Gases are gradually siphoned off their surfaces and swirl into the abyss. The remains of the star soon follow.

That process is what Eikenberry is hoping to document.

He and a research assistant have compiled a list of 26 stars. All appear to be in the center of our galaxy, and all are emitting large amounts of X-rays - a sign that something catastrophic is happening to them. To test his theory that the stars are being cannibalized by a black hole, Eikenberry has come to Mauna Kea for four days of observing.

It is, in essence, a fishing expedition. The chances for success depend upon skill, persistence, luck and weather.

The heights that make Mauna Kea so frigid also make it one of the best places in the world for stargazing. There is less of Earth's atmosphere to distort the stars. It is dark, isolated, and even when it rains, the clouds are usually just scenery far below, blanketing the sparsely developed "Big Island" - the youngest, largest and southernmost member of the Hawaiian archipelago.

But now, the vestiges of a stubborn storm system linger over the mountain, obscuring the stars. Eikenberry is worried. His first two nights of observing already have been stymied by the storm. He parks the SUV in a small, pitch-dark parking lot and cranes his neck to see the sky in the direction of Sagittarius, high overhead.

To people who know their constellations, Sagittarius is the archer. But to astronomers it marks the bustling center of our Milky Way galaxy, a glowing dome so crowded that if the sun and Earth were transplanted there, 25,000 light-years away, the stars in our skies would turn night to day.

The galactic center is also filled with hundreds, even thousands, of compact objects. The archer points the way to Eikenberry's hunting grounds.

But like dust swirling through a construction zone, interstellar debris obscures our view. Only recently have scientists been able to begin mapping the galactic center. So any information Eikenberry can glean about its black holes could lead to research papers and collaborations with other astronomers.

The thick metal door slams in a windblown clatter as Eikenberry and his graduate assistant slip into the control room of the National Aeronautics and Space Administration's Infrared Telescope Facility, or IRTF.

Engineers and astronomers have designed and assembled the instruments in their Gainesville, Fla., lab, after competing with other research institutions for lucrative contracts from observatories that need ever-more-complex light-gathering equipment to answer questions about the universe.

UF instruments - some with decals of the school's Gator mascot surreptitiously stuck on their sides - have been installed in observatories all over the world.

All the UF devices are infrared, meaning that they do not collect visible light, but light from a part of the spectrum unobservable by the human eye.

They may not sound flashy. They may not produce astonishing, poster-ready, full-color photos of nebulae in bloom, as the Hubble Space Telescope has. But they are the instruments that will be doing much of the heavy lifting in astronomy for decades, as researchers try to answer fundamental questions about the development of planets, suns, galaxies and the universe itself.

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