Neutron StarHubble observes fast-moving Neutron Star
CNN.com, November 9, 2000
What's as big as Manhattan Island, 10 trillion times denser than steel and 100 times faster than a supersonic jet? That would be the runaway neutron star RX J185635-3754, the closest of its type ever observed. Its trajectory was caught in three Hubble snapshots taken in 1996 and 1999. A neutron star is the super-dense remnant of a collapsed star, composed entirely of neutrons. This particular one is the product of a stellar explosion that would have been visible to our distant ancestors in 1 million B.C., astronomers with the Space Telescope Science Institute said Thursday. Now located 200 light-years away in the southern constellation Corona Australis, it will swing by Earth at a safe distance of 170 light-years in about 300,000 years, astronomers said in a statement. A light-year is the distance traveled by light in a full year (about 6 trillion miles).
"The scientific importance of this object lies in the fact that the neutron star is isolated," said Frederick M. Walter of the State University of New York. "Because this is the closest and brightest of the few known isolated neutron stars, it is the easiest to study and is an excellent test bed for nuclear astrophysical theories." From an earthly perspective, RX J185635-3754 travels across the sky a distance equal to the diameter of the moon every 5,400 years. Although this apparent motion may seem slow, it is actually one of the fastest moving stars in the sky, astronomers said. The Hubble results have been accepted for publication in the Astrophysical Journal. The Hubble Space Telescope a joint project of NASA and the European Space Agency.
