dipper@utastro.UUCP (Debbie Byrd) (05/13/85)
Astronomers are pondering a cloud of neutral hydrogen gas adrift in the space between galaxies. More -- after this. May 13 Gas Between the Galaxies Overhead in the May night sky -- as far away as the distant galaxies -- there's a cloud of neutral hydrogen gas drifting by itself -- not connected to any galaxy. On a grand scale, the universe is made of galaxies -- and galaxies are made of both stars and gas. But this enormous lone cloud of gas in space was something new when it was discovered in 1983. It was the first such cloud known, although the process which may have set the cloud adrift in space has been discussed for some years. No one knows for sure how the cloud got there. But it's possible that it was left behind when two galaxies collided. When galaxies collide, the stars themselves don't meet -- because stars are tiny on the grand scale of galaxies -- and separated by vast gulfs of space. In fact, in terms of their stars, colliding galaxies merely pass through each other -- like ghosts. But there's also gas in galaxies. And during a collision, the gas in one galaxy slams into the gas of the other. The galaxies can be stripped of their gas -- and a cloud of gas left behind. The great newly-discovered cloud of neutral hydrogen gas is located in deep space -- in the direction of the constellation Leo. It could be the result of a collision between galaxies. Or it might be a fragment of the original gas from the beginning of the universe, which has not yet condensed into a galaxy. Astronomers are working hard to study this cloud -- over its distance of some 30 million light-years. Script by Deborah Byrd. (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin