High-energy gamma-ray results from the second small astronomy satellite.

But the dozens of optical and radio observatories on the ground are complemented by very few astronomy satellites.

It will be China's first astronomy satellite.

The next purely Soviet space astronomy satellites will involve only the relatively simple hardware of radio telescopes (Box above).

The costs involved in astronomy satellites cover much more than the detectors or telescopes and even the cheapest astronomical satellite now costs around £60 million.

But this had remained only educated conjecture, until the flight of the Infrared Astronomy Satellite in 1983.

The controllers congratulated the spacewalking repairmen for their swift work in saving the mission of the 17-ton $600-million astronomy satellite.

First detected by the Infrared Astronomy Satellite at wavelengths of 60 and 100 micrometres.

The sporadic signals were in the form of ultraviolet laser light targeted on an antiquated astronomy satellite in Earth orbit.

Dr. Bless, the University of Wisconsin astronomer, said he and his colleagues had serious trouble with an astronomy satellite lofted in 1968.