Monday, June 7, 1999 Published at 16:56 GMT 17:56 UK
Most distant galaxy found
Radio wave contours make a double pattern
By BBC News Online Science Editor Dr David Whitehouse
Astronomers have discovered the most distant galaxy yet found. It was detected because it gives off radio waves.
Hidden in the galaxy is thought to be the most-distant black hole discovered so far. Black holes are massive objects that only flare with light when they engulf nearby stars.
The discovery was made by astrophysicist Wil van Breugel of the Lawrence Livermore Laboratory in the US.
Far, far away
The newly-discovered radio galaxy, designated TN J0924-2201, was found toward the southern constellation of Hydra at a distance of nearly 11 billion light years from Earth.
The radio waves emitted by radio galaxies are thought to be powered by beams of extremely hot gas coming from super-massive black holes buried at their cores.
The nearest and first-known radio galaxy, Cygnus A, was discovered nearly 50 years ago. The newly-discovered radio galaxy is 200 times more distant, 30 times more luminous, and was born when the Universe was still very young.
The discovery of TN J0924-2201 was made possible by using several newly-available tools to astronomers, including deep radio surveys, large optical telescopes and infrared detectors, van Breugel said.
"The new, large optical telescopes allow astronomers for the first time to begin exploring the 'Dark Ages', when the Universe was very young and the first stars and black holes were born. Radio galaxies may lead the way."
The image of the radio galaxy was obtained with the Keck Observatories twin giant telescopes situated on the Mauna Kea extinct volcano in Hawaii. Each telescope has a mirror 10 m (400 inches) across.
The galaxy was young and faint and is near the limits of detectability.
It was still in the process of forming through the merging of smaller galaxies. As such it was a chaotic collection of hot young stars.
Over billions of years it will have settled down and may have evolved into a galaxy like our own Milky way.