The Orbiting Astronomical Observatory 2 (OAO-2, nicknamed ''Stargazer'') was the first successful
space telescope
A space telescope or space observatory is a telescope in outer space used to observe astronomical objects. Suggested by Lyman Spitzer in 1946, the first operational telescopes were the American Orbiting Astronomical Observatory, OAO-2 launch ...
(first space telescope being
OAO-1, which failed to operate once in orbit), launched on December 7, 1968.
An
Atlas-Centaur
The Atlas-Centaur was a United States expendable launch vehicle derived from the SM-65 Atlas D missile. Launches were conducted from Launch Complex 36 at the Cape Canaveral Air Force Station (CCAFS) in Florida.
Early development
Convair, ...
rocket launched it into a nearly circular altitude Earth orbit. Data was collected in ultraviolet on many sources including comets, planets, and galaxies.
[ It had two major instrument sets facing in opposite directions; the Smithsonian Astrophysical Observatory (SAO) and the Wisconsin Experiment Package (WEP).][Orbiting Astronomical Observatory OAO-2]
/ref> One discovery was large halos of hydrogen gas around comets,[ and it also observed Nova Serpentis, which was a nova discovered in 1970.][
]
Celescope: Smithsonian Astrophysical Observatory
The Smithsonian Astrophysical Observatory, also called Celescope, had four 12 inch (30.5 cm) Schwarzschild telescopes that fed into Uvicons.[High-Resolution Telescopes]
/ref> Various filters, photocathode
A photocathode is a surface engineered to convert light (photons) into electrons using the photoelectric effect. Photocathodes are important in accelerator physics where they are utilised in a photoinjector to generate high brightness electron be ...
s, and electronics aided in collecting data in several ultraviolet light
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiatio ...
passband
A passband is the range of frequencies or wavelengths that can pass through a filter. For example, a radio receiver contains a bandpass filter to select the frequency of the desired radio signal out of all the radio waves picked up by its antenn ...
s.[ The experiment was completed in April 1970.][ By the time it finished about 10 percent of the sky was observed.][ The Uvicon was an ultra-violet light detector based on the Westinghouse ]Vidicon
Video camera tubes were devices based on the cathode ray tube that were used in television cameras to capture television images, prior to the introduction of charge-coupled device (CCD) image sensors in the 1980s. Several different types of tubes ...
.electron
The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family,
and are generally thought to be elementary particles because they have n ...
s which were in-turn converted to a voltage as those electrons hit the detection area of the tube. There has been a Uvicon in the collection of the Smithsonian Institution
The Smithsonian Institution ( ), or simply the Smithsonian, is a group of museums and education and research centers, the largest such complex in the world, created by the U.S. government "for the increase and diffusion of knowledge". Found ...
since 1973.
Wisconsin Experiment Package
The Wisconsin Experiment Package had eleven different telescopes for ultraviolet observations.[Wisconsin Experiment Package]
/ref> For example, there was a photoelectric photometer fed by a 16-inch (40.64 cm) telescope with a six-position filter wheel.[ WEP observed over 1200 targets in ultraviolet light before the mission ended in early 1973.][
]
Spacecraft bus
The observatory was built in the shape of an octagonal prism
In geometry, the octagonal prism is the sixth in an infinite set of prisms, formed by rectangular sides and two regular octagon caps.
If faces are all regular, it is a semiregular polyhedron.
Symmetry
Images
The octagonal prism can also ...
. It measured about and weighed .
See also
* Orbiting Astronomical Observatory
* Orbiting Solar Observatory
The Orbiting Solar Observatory (abbreviated OSO) Program was the name of a series of American space telescopes primarily intended to study the Sun, though they also included important non-solar experiments. Eight were launched successfully int ...
References
External links
OAO 2 observations of the Alpha Persei clusterOAO-2 Info and pics50th Anniversary Overview of OAO-2 including video
Ultraviolet telescopes
Spacecraft launched in 1968
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