dipper@utastro.UUCP (Debbie Byrd) (08/22/84)
There's evidence for solid material around more than 40 nearby stars in our galaxy. More about it -- right after this. August 22 Stars with Possible Solar Systems Last year IRAS -- the Infrared Astronomical Satellite -- discovered particles of solid material in orbit around the star Vega. Later, a second star -- Fomalhaut -- was also found by IRAS to be orbited by some kind of solids, possibly in the form of small grains. Well, since then, more than forty additional stars have been discovered by IRAS to show excess infrared emission -- indicating that these stars as well may have solid material in orbit around them. More work is needed -- but the evidence suggests that many stars in our galaxy may be accompanied by disks of orbiting grains -- which may be on the road toward evolving into full-fledged planets and solar systems. More than three hundred stars within 75 light-years of Earth have been examined so far in the IRAS data -- to reveal more than 40 stars with possible solids in orbit around them. Many of these stars are similar to our sun in terms of luminosity, mass, and age. Still, no actual full-sized planets have been found. The Infrared Astronomical Satellite -- or IRAS -- is very good at detecting clouds of dust and icy particles -- but not so good at spotting planet-sized bodies. Still, the studies of stars with possible orbiting grains of material will help scientists understand how planets may form -- as well as determine which stars are most likely to have planets in advanced stages of evolution. IRAS was launched into orbit by NASA on January 25, 1983. During its ten-month mission, it measured infrared emission from more than two hundred and fifty thousand objects in space. Script by Deborah Byrd. (c) Copyright 1983, 1984 McDonald Observatory, University of Texas at Austin