After 20 years of planning, developing and constructing, astronomers at the Max Planck Institute for Astronomy have finally released the first image captured by the new Large Binocular Telescope, an instrument with a light-gathering power 24 times greater than the Hubble Space Telescope. The so-called LBT, an American-German-Italian joint venture stationed on the 3,190-meter-high Mt. Graham in Arizona, will be able to image planets circling distant stars and is poised to help answer fundamental questions about the universe, including how galaxies, stars and planets evolved from the big bang.
"The LBT will open completely new possibilities in researching planets outside the solar system and the investigation of the farthest--and thus youngest--galaxies," says Thomas Henning of the Max Planck Institute for Astronomy. To date, a handful of impressive ground-based telescopes have provided astronomers with important insights about the universe. For example, they have learned that stars form in dense cloudlike features within galaxies. But observing the intricacies of star birth is difficult with these telescopes because the radiating energy of low-mass stars and brown dwarfs is not bright enough to be visible and interstellar dust can obscure views. The Hubble Space Telescope has helped overcome some of these problems, but this kind of instrument is expensive to build, launch and maintain.
Now a combination of advanced optics, instrumentation and high-power computers is making it possible for ground-based telescopes, particularly those situated on high mountaintops, to see deeper into space than ever before at a fraction of the cost. The LBT can resolve faint objects because it has two large mirrors--each 8.4 meters in diameter--that focus like field glasses for viewing. By combining the two views, the instrument is able to collect as much light as a single telescope with an 11.8-meter mirror. By comparison, the Hubble Space Telescope's mirror is 2.4 meters in diameter.
But the LBT doesn't rely only on its mirrors. It uses optics designed to adapt to observing conditions and it works with a combination of specialized instruments that can do such things as gather infrared images, detect the composition of the surface of stars, compensate for the blurring caused by turbulence in Earth's atmosphere, and boost image sharpness to a quality far better than that of Hubble.
For the "first light" image, astronomers used just one of LBT's mirrors to capture a spiral galaxy in the constellation Andromeda. In the future, they will use both mirrors to conduct a number of studies, including observing the Jupiterlike planets known to be revolving around our nearest neighboring stars.