The world's most sensitive listening device is about to hear more from the universe.

　　The radio telescope at Puerto Rico's Arecibo Observatory, powerful enough to hear planets forming several billion light years away, is receiving six more radio receivers to expand its range, scientists said on Monday.

　　Once the upgrade, nicknamed the ALFA Project, is completed next year, the observatory's staff of 15 scientists will take on the arduous task of mapping the night sky for future generations.

　　The map with its collection of detailed data about location, identity and properties of what is in space will go far beyond anything currently in use, researchers say.

　　No such map has been made until now because the scale was too big, said observatory director Daniel Altschuler. When finished it will be a "national treasure, a legacy, so to speak."

　　"We're searching in the dark with a tiny, little flashlight, only now we will have a much bigger flashlight," he said. With the US million upgrade, Arecibo should find thousands of new pulsars, supernova, black holes and planets, "and some of those are going to be very interesting."

　　The 1,000-foot-wide parabolic receiver - composed of 38,000 aluminum tiles - allows researchers to listen to sounds in space instead of depending on optics, like the orbiting Hubble Space Telescope.

　　The information gathered will be compiled in a worldwide database scientists can access on the Internet, said Tony Acevedo, head of Arecibo's scientific services.

　　"The idea is that it is public," Acevedo said on Monday. "Scientists can use it as they wish."

　　The observatory and its gargantuan dish were built in 1963 by the US Department of Defense. It is now run by Cornell University under the National Foundation of Science.

　　The telescope's 1974 discovery of a twin neutron stars won a pair of scientists the Nobel Prize in 1993 by proving Albert Einstein's theory of gravity waves. Other finds include ice on Mercury and the first known planets outside our solar system.