PASADENA, Calif. -- Astronomers have photographed for the first time evidence indicating a previously unknown solar system exists around a star twice as big and 10 times as bright as the sun, scientists announced Monday.
Dr. Bradford Smith, of the University of Arizona, said the photographs reveal a vast swarm of solid particles that form a disk 40 billion miles in diameter around Beta Pictoris, a star about 50 light years from Earth.
Earlier this year, infrared radiation detected the first evidence of the disk and raised the possibility that another solar system may exist. The photographs provide the first visual proof to support the finding.
'The indications are fairly good we are seeing another solar system, although we can't actually prove there are planets around this star,' Smith said in a telephone interview from Hawaii.
Smith, who teamed with Richard Terrile of NASA's Jet Propulsion Laboratory, said the significance of the discovery is partly 'philosophical.'
'It shows our own solar system is not unique,' he said. 'There are many who believe that the fact that our sun has planets around is some strange thing that happened. What we now know is that there is another example of it and there are good indications there are many, many more.
'Other solar systems exist and other planets, and, if one wants to extrapolate that, that other life exists.'
The particles that compose the disk, ranging from tiny grains to chunks a few miles across, are probably made of ices, silicates and organic carbon compounds -- the same materials that compose the planets of our solar system, he said.
Because it is so flat, scientists believe the disk is no more than a few hundred million years old, a youngster compared with our own solar system, which is 4.5 billion years old.
An older solar system would not be so flat and would have ejected much of its debris into interstellar space, Smith said.
The astronomers' interest in Beta Pictoris was peaked earlier this year by reports from the Infrared Astronomical Satellite, or IRAS, that revealed very high levels of infrared radiation around it and three other similar stars, indicating the existence of solid material in orbit.
Using a specially equipped 100-inch telescope at the Las Campanas Observatory near La Serena, Chile, the astronomers made the photographs, but it was not until they had been processed by computer that the two faint streaks of light extending outward appeared.
To the naked eye, Beta Pictoris appears as a faint star in Pictor, an obscure constellation in the southern skies. For Americans, it can only been seen clearly from the extreme southern parts of the country. It remains permanently below the horizon to most people in the Northern Hemisphere.
