Orbiting Astronomical Observatory 2

From Wikipedia, the free encyclopedia
  (Redirected from OAO-2 Stargazer)
Jump to: navigation, search
Orbiting Astronomical Observatory 2
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 (1968-12-07UTC08:40:09) UTC
Rocket Atlas SLV-3C Centaur-D
Launch site Cape Canaveral LC-36B
End of mission
Last contact January 1973 (1973-02)
Orbital parameters
Reference system Geocentric
Regime Low Earth
Perigee 768 kilometres (477 mi)
Apogee 777 kilometres (483 mi)
Inclination 35.0 degrees
Period 100.30 minutes
Epoch 6 January 1969[1]

The Orbiting Astronomical Observatory 2 (OAO-2, nicknamed Stargazer) was a space observatory launched on December 7, 1968.[2] An Atlas-Centaur rocket launched it into a nearly circular 750-kilometre (470 mi) altitude Earth orbit.[3] Data was collected in ultraviolet on many sources including comets, planets, and galaxies.[2][4] It had two major instrument sets facing in opposite directions; the Smithsonian Astrophysical Observatory (SAO) and the Wisconsin Experiment Package (WEP).[4] One discovery was large halos of hydrogen gas around comets,[4] and it also observed Nova Serpentis.[2]

The Smithsonian Astrophysical Observatory, also called Celescope, had four 12 inch Schwarzschild telescopes that fed into Uvicons.[5] Various filters, photocathodes, and electronics aided in collecting data in several ultraviolet light passbands.[5] The experiment was completed in April 1970.[5] By the time it finished about 10 percent of the sky was observed.[5]

The Wisconsin Experiment Package had eleven different telescopes for ultraviolet observations.[6] For example, there was a photoelectric photometer fed by a 16-inch telescope with a six-position filter wheel.[6] WEP observed over 1200 targets in ultraviolet light before the mission ended in early 1973.[4]

See also[edit]


External links[edit]