dipper@utastro.UUCP (Debbie Byrd) (01/20/86)
Astronomers have observed a ring of dust around a newly formed star. More on the birth of stars -- after this. January 20 Doughnut Dust and Baby Stars Stars are born out of interstellar clouds of dust and gas -- called nebulae. There is gravitational attraction between particles in the nebula. Eventually, enough material falls together via gravity to form a new star. Astronomers have been carefully observing disk-shaped concentrations of gases and dust in nebulae -- looking for possible new stars in the center of such disks. Recently astronomers made the first clear observation of a disk with a hole in its center. This disk is in a nebula called Sharpless l06 -- located in the constellation Cygnus the Swan. The doughnut shape of the disk is evidence that a new star has formed in the center of the cloud. The star would be separating from the surrounding ring of dust. We can't see the baby star itself yet. The visible light the star radiates is effectively blocked by the surrounding dust. But this dust is being heated by the star -- and the dust emits radiation in the far infrared region of the spectrum. Astronomers used special equipment aboard an airplane -- NASA's Kuiper Airborne Observatory -- to observe this ring of dust in the infrared. The equipment had to be kept very cold -- because to see infrared radiation, the detector has to be cooler than the object being looked at. Liquid helium was used to cool the detector to about a degree and a half above abolute zero. This cool system gave us the first clear proof of a new star separating from a surrounding dust cloud. Billions of years ago our own sun may have started its life in much the same way. Script by Diana Hadley. (c) Copyright 1985, 1986 McDonald Observatory, University of Texas at Austin