All Things Considered, March 17, 2008
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The best pair of eyes on Earth are now wide open. The Large Binocular Telescope sits in a 17-story building atop an Arizona mountain.
LBT, as it's known for short, can probe deeper into the cosmos than any other instrument. The 580-ton telescope is twice as big as the next-largest telescope on Earth, and it has 10 times the resolution of the Hubble Space Telescope. The LBT cannot see farther than Hubble, but the images it sends back are much sharper and of a much wider field than the space telescope.
In the control room, Richard Pogge, professor of astronomy at Ohio State University, types in coordinates for this night's viewing. He and a half-dozen others sit in a room filled with computer screens.
There's a universe to look at, but time is limited, so scientists submit proposals for observation. One of the first for tonight: the Kuiper Belt, which lies on the edge of the solar system, about 2.7 billion miles from Earth.
How small? Well, Pluto is roughly 1,200 miles wide. The LBT can see ice balls in the same region that are one or two miles wide. The cameras take an exposure – which lasts five minutes — and then the image is revealed on a computer screen. It looks like a field of stars. But take the same picture six nights in a row and — if you know what you're looking for — you can see the ice balls moving.
And with the data this telescope gathers, Pogge says you can see a lot more, including how far are away an object is, what it is made of, what its mass is and how fast it's moving away from us.
Answering Questions About the Universe
Notre Dame professor Peter Garnevich helps focus the LBT on another object, which is no small task given the instrument's complexity. Garnevich is interested in a supernova that exploded a few nights earlier.
"The star just happened to die and its jet was pointed at us and we can see it most of the way across the universe," says Garnevich.
The screen shows a large mass with a plume coming from it. Garnevich wants to learn how energy from the dying star decays over time. By looking at objects like this — halfway across the universe and back in time — these astronomers hope the LBT will answer some fundamental questions.
Pogge lists some of those questions: "Where do we come from, how did we get here, where are we going? Astronomy's one of the few ways we can answer that."
Over the next few years, many more devices will be added to the LBT to enhance its capabilities. That should be enough to keep astronomers happy at night for decades.