Allen Telescope Array is a radio telescope designed to search for signs of intelligent life in the universe. It is also used to study radio noise from objects in space. The Allen Telescope Array is in Hat Creek (east of Redding), California, in the Cascade Mountains. It is a joint project of the SETI Institute and the University of California at Berkeley. SETI stands for the Search for Extraterrestrial Intelligence.
Researchers from the SETI Institute used the telescope to search for signals broadcast from nearby star systems by intelligent beings. If such beings exist, they might send out radio signals to get someone’s attention. Even if they are not trying to communicate with other worlds, they may simply use technologies similar to broadcast television, radio, and radar. Such technologies could generate signals we might listen in on. Berkeley scientists used the telescope to study the natural radio static coming from galaxies, gas clouds, and other objects. Unlike telescopes that use visible light, the sun does not interfere with radio telescopes like the Allen Telescope Array, and they can thus be used 24 hours a day.
The Allen Telescope Array is an array (connected arrangement) of many small radio antennas, rather than a single large dish. There are two reasons for building a radio telescope in this way. First, it is less expensive. Second, the array can make highly detailed “radio maps” of the sky by combining the signals from all the antennas. Each of the array’s dishes measures about 20 feet (6 meters) in diameter.
The Allen Telescope Array began operating in October 2007 with 42 antennas. In 2011, the National Science Foundation reduced funding for the telescope. The loss of funds forced the telescope to cease operations in April. The telescope resumed operation in late 2011 with funding from the United States Air Force and public donations.
See also SETI Institute
