Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, April 7, 1994 TAG: 9404070322
SECTION: NATL/INT PAGE: A-9 EDITION: METRO
SOURCE: The New York Times
DATELINE: LENGTH: Medium
The stellar explosion, designated SN1994I, meaning the ninth one to be detected this year, was observed in the Whirlpool Galaxy, or M51, by several amateur and professional astronomers in the United States and Japan.
The explosion occurred 15 million years ago, but because of the galaxy's distance, light from it only now is reaching Earth.
Astronomers said the supernova would never match the luminosity of the spectacular event observed in the Southern Hemisphere in 1987. One of the nearest supernovas in centuries, the one in 1987 occurred next door in astronomical terms, 150,000 light-years away near the Large Magellanic Cloud, a companion galaxy to the Milky Way.
Unlike the 1987 event, the new supernova is not visible to the unaided eye and is not expected to be. Even backyard astronomers may have trouble seeing it unless they have at least a 20-inch telescope.
But because the object can be observed from the Northern Hemisphere, it should lend itself to more intense scrutiny by telescopes on the ground and in space.
Dr. Kurt W. Weiler, an astronomer at the Naval Research Laboratory in Washington, D.C., said that, on average, supernovas this bright occur only twice every decade. But this one may be even more unusual.
On Sunday, radiotelescopes in New Mexico already were detecting radio signals from the explosion, something Weiler said had never happened this early for any previously observed supernova.
Normally, radio waves are detectable no earlier than three or four days after the first visible light is seen.
by CNB