Printer Friendly

Falling into a black hole.

Falling into a black hole

The current standard theory of quasars proposes that these bright, starlike, but extragalactic objects have black holes at their centers. The extremely high flux of radiation coming out of a quasar is generated by the gravitational energy of matter falling into the black hole. Plenty of secondary evidence supports this picture. Now Martin Gaskell of Ohio State University in Columbus presents what seems to be the first direct evidence for gas falling into a black hole.

The evidence comes from studies of the spectra taken by the International Ultraviolet Explorer satellite of the radiation from a gas cloud in the galaxy NGC 4151. Analysis of the details of the shapes of the lines in these spectra show that the predominant motion of the cloud is inward, Gaskell says. He believes he can exclude outflow to a 99.9 percent confidence limit. From knowledge of this inflow he can estimate the mass of the black hole at 60 million times that of the sun. It may be the center of a very weak quasar, he says, and he concludes, "Accretion [of matter] on black holes in quasars is now on an observational footing."
COPYRIGHT 1986 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1986, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Author:Thomsen, Dietrick E.
Publication:Science News
Date:Jul 19, 1986
Words:197
Previous Article:Seeing the cell and letting it live.
Next Article:For those who don't read Japanese.
Topics:


Related Articles
Astro eyes new signs of black holes.
An outburst of stellar knowledge.
Hubble finds an off-center black hole.
Firm evidence of Milky Way black hole.
Probing the heart of extragalactic jets.
Chandra eyes low-temperature black hole.
Peering at black holes: an eventful look.
Galaxy's Black Hole: X Rays Mark Spot.
Stellar spectacular: brightest supernova.
Sitka champ in trouble.

Terms of use | Copyright © 2017 Farlex, Inc. | Feedback | For webmasters