Names | OAO-A2, OAO2 |
---|---|
Mission type | Astronomy |
Operator | NASA |
COSPAR ID | 1968-110A |
SATCAT no. | 3597 |
Spacecraft properties | |
Manufacturer | Grumman |
Dry mass | 2,012 kilograms (4,436 lb) |
Start of mission | |
Launch date | 7 December 1968, 08:40:09 | UTC
Rocket | Atlas SLV-3C Centaur-D |
Launch site | Cape Canaveral LC-36B |
End of mission | |
Disposal | Telescope issues |
Deactivated | February 1973[1] |
Orbital parameters | |
Reference system | Geocentric |
Regime | Low Earth |
Perigee altitude | 768 kilometres (477 mi) |
Apogee altitude | 777 kilometres (483 mi) |
Inclination | 35.0 degrees |
Period | 100.30 minutes |
Epoch | 6 January 1969[2] |
The Orbiting Astronomical Observatory 2 (OAO-2, nicknamed Stargazer) was the first successful space telescope (first space telescope being OAO-1, which failed to operate once in orbit), launched on December 7, 1968.[3] An Atlas-Centaur rocket launched it into a nearly circular 750-kilometre (470 mi) altitude Earth orbit.[4] Data was collected in ultraviolet on many sources including comets, planets, and galaxies.[3][5] It had two major instrument sets facing in opposite directions; the Smithsonian Astrophysical Observatory (SAO) and the Wisconsin Experiment Package (WEP).[5] One discovery was large halos of hydrogen gas around comets,[5] and it also observed Nova Serpentis, which was a nova discovered in 1970.[3]