ROSAT was a German Aerospace Center

German Aerospace Center

The German Aerospace Center is the national centre for aerospace, energy and transportation research of the Federal Republic of Germany. It has multiple locations throughout Germany. Its headquarters are located in Cologne. It is engaged in a wide range of research and development projects in...

-led satellite X-ray telescope

X-ray telescope

An X-ray telescope is a telescope that is designed to observe remote objects in the X-ray spectrum. In order to get above the Earth's atmosphere, which is opaque to X-rays, X-ray telescopes must be mounted on high altitude rockets or artificial satellites.-Optical design:X-ray telescopes can use...

, with instruments built by Germany, the UK and the US. It was launched on 1 June 1990, on a Delta II

Delta II

Delta II was an American space launch system, originally designed and built by McDonnell Douglas. Delta II is part of the Delta rocket family and was in service from 1989 until November 1, 2011...

 rocket from Cape Canaveral

Cape Canaveral

Cape Canaveral, from the Spanish Cabo Cañaveral, is a headland in Brevard County, Florida, United States, near the center of the state's Atlantic coast. Known as Cape Kennedy from 1963 to 1973, it lies east of Merritt Island, separated from it by the Banana River.It is part of a region known as the...

, on what was initially designed as an 18 month mission, with provision for up to five years of operation. ROSAT actually operated for over eight years, finally shutting down on 12 February 1999.

In February 2011, it was reported that the 2400 kg (5,291 lb) satellite was unlikely to burn up entirely while re-entering the Earth's atmosphere due to the large amount of ceramics and glass used in construction.