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New Astronomy: Romance Fades as Technology Takes Over
By Tariq Malik
Staff Writer
posted: 07:00 am ET
27 August 2002
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LEDE When Galileo Galilei first pointed his telescope at Jupiter nearly four centuries ago, his tools were rather simple -- a tube, some lenses and a lot of patience to observe the sky night after night. But astronomers these days see space differently. In fact, they don't really "see" it at all, since most of them use computers to do the observing. Ever-advancing technology has eroded the romance of practicing astronomy, replacing human observers with mechanical detectors that see far better than an astronomer with 20-20 vision. Galileo might be surprised, maybe even dismayed, at the evolution his simple tool has undergone. able -->  | | SCIENCE TUESDAY | | | | | |  |  | Images |
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 | Galileo Galilei discovered four moons (Io, Europa, Ganymede and Callisto) circling Jupiter in 1610 with a telescope he built himself. Galileo's homespun astronomy observations also included the Moon, Venus, and helped show that the Earth and other planets revolved around the Sun, and not the other way around. Click to enlarge.
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| One of the foremost astronomers of the 20th Century, Edwin Hubble lived from 1889 to 1953 and is shown above posing with the 48-inch telescope on Palomar Mountain and his famous pipe. Hubble's hands-on research helped determine existence of other galaxies, as well as the universe's expansion. The Hubble Space Telescope is named after him. Click to enlarge.
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| Charge Coupled Devices (CCDs), like this one made for one of the telescopes at the W.M. Keck Observatory, serve are the go-to tool for modern astrononical observation. Click to enlarge.
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| The laser light that creates the virtual star is seen emanating from a device attached to the Keck II telescope.
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| | |  | Related SPACE.com STORIES |
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|  | TODAY'S DISCUSSION | | | | | | | "It's not just the fact that we don't look through the telescopes anymore," says James Beletic, deputy director of the W. M. Keck Observatory atop Hawaii's Mauna Kea. "It's that it's almost impossible to do it now, with all the detectors we have attached to our telescopes here." With a pair of 33-foot (10-meter) telescopes weighing 300 tons each, Keck is the largest optical system on Earth. While the telescopes are 14,000 feet up an extinct volcano, astronomers control them from a separate center at an altitude of only 2,500 feet -- miles away. Controlling the telescopes by remote, Beletic told SPACE.com, is better than operating them at high altitude where the thin air can affect astronomer's concentration and lead to mistakes. There is also an ongoing push to move astronomers further and further away from their equipment. And, of course, remote telescope control is essential in space, where observatories like NASA's Hubble Space Telescope and Chandra X-ray Observatory carry out observations impossible to make from the ground. "Nowadays, if you're not behind the telescope, then you're in a room behind the telescope," Beletic said. "And if you're in a separate room, you might as well be 18 miles away." Stepping away from the eyepiece Replacing the human eye with a light collector is nothing new. Astronomers in the mid-1800s were pointing cameras at the sky to track changes in star and planet positions. Up through the 1970s, scientists attached photographic plates to telescopes that, after lengthy exposures, produced photos that helped determine star size, brightness and weight. Since then, charge coupled devices (CCDs), which are electronic light detectors also found in household video cameras, have replaced the plates and become the lynchpin of modern astronomy."It's mostly a matter of convenience," said University of Illinois astronomer Laird Thompson in a telephone interview. "When I first started in astronomy, I was literally out in the cold making observations, and you'd always have to be there to change the photographic plates. These days, all you do is push buttons at the computer." The romantic side of astronomy may suffer, Thompson says, but at least your feet stay warm. CCDs record light patterns much like regular film, yet they are more sensitive (photographic plates typically capture only about 1 percent of the light coming through a telescope). CCDs are therefore capable of detecting much fainter objects. They are the go-to detectors for most professional astronomers and even some amateurs. Thompson uses a CCD on a 100-inch (2.5-meter) telescope atop Mount Wilson near Pasadena, California to push the capabilities of the telescope. His innovative project, which uses a laser to create an artificial guide star and a system known as adaptive optics to cancel out the blurring effect of the atmosphere, is aimed at producing the clearest images of stars and other objects from an earthbound station. Some of the pictures produced with adaptive optics, Thompson said, are clearer than those taken by Hubble, simply because the ground telescopes are bigger. Hubble's aperture spans about eight feet (2.4 meters), while the largest telescopes on Earth, the Keck twins in Hawaii, are four times that size. Plans are even underway to build even larger ground-based skywatching tools. "There are proposals for telescopes with apertures of 30 meters, 50 meters and even 100 meters," Thompson said. "That's bigger than a football field." Next Page: More than meets the eye
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%20circling%20Jupiter%20in%201610%20with%20a%20telescope%20he%20built%20himself.%20Galileo's%20homespun%20astronomy%20observations%20also%20included%20the%20Moon,%20Venus,%20and%20helped%20show%20that%20the%20Earth%20and%20other%20planets%20revolved%20around%20the%20Sun,%20and%20not%20the%20other%20way%20around.%20Click%20to%20enlarge.)
,%20like%20this%20one%20made%20for%20one%20of%20the%20telescopes%20at%20the%20W.M.%20Keck%20Observatory,%20serve%20are%20the%20go-to%20tool%20for%20modern%20astrononical%20observation.%20Click%20to%20enlarge.)
