 Test inflation of PAGEOS, 5 August 1965 | |
| Names | PAGEOS-A |
|---|---|
| Operator | NASA Office of Space Applications |
| COSPAR ID | 1966-056A |
| SATCAT no. | 02253 |
| Spacecraft properties | |
| Launch mass | 56.7 kg (125 lb) |
| Dimensions | 30.48 m (100.0 ft) diameter[1] |
| Start of mission | |
| Launch date | 00:14:00, June 24, 1966 (UTC) |
| Rocket | Thrust augmented Thor-Agena D |
| Launch site | Vandenberg AFB |
| End of mission | |
| Destroyed | partially disintegrated July 1975 |
| Orbital parameters | |
| Reference system | Geocentric[2] |
| Eccentricity | 0.00301 |
| Perigee altitude | 4,207 km (2,614 mi) |
| Apogee altitude | 4,271 km (2,654 mi) |
| Inclination | 87.14° |
| Period | 181.43 min |
| Epoch | 24 June 1966 |
PAGEOS (PAssive Geodetic Earth Orbiting Satellite) was a balloon satellite which was launched by NASA in June 1966.[1] It was the first satellite specifically launched for use in geodetic surveying,[3] or measuring the shape of the earth, by serving as a reflective and photographic tracking target. At the time, it improved on terrestrial triangulations of the globe by about an order of magnitude.[4] The satellite, which carried no instrumentation, broke up between 1975 and 1976.[5] One of the largest fragments of the satellite finally deorbited in 2016.[6]
PAGEOS was part of a larger program of inflatable satellites that grew from the original concept by William J. O'Sullivan of a 30-inch diameter inflatable satellite in 1956 to measure air drag at high altitudes, called the Sub-Satellite.[7] While the Sub-Satellite failed, the idea of a visible US satellite became very attractive after Sputnik launched in the Cold War, resulting in a program of similar, larger satellites.[7] These included satellites Echo 1 and Echo 2 under Project Echo, which were also used for experiments in geodetic surveying;[3] several air-density-focused Explorer satellites; and finally PAGEOS.[7]
- ^ a b "PAGEOS 1". National Aeronautics and Space Administration. Retrieved March 16, 2017.
- ^ "NSSDCA – PAGEOS 1 – Trajectory Details". nssdc.gsfc.nasa.gov. NASA. Retrieved June 22, 2016.
- ^ a b "Modern Surveying". Encyclopaedia Britannica. Retrieved March 24, 2024.
- ^ Kleusberg, Alfred (2003). "Satelliten im Dienst der Geodäsie und Geoinformatik" (PDF). University of Stuttgart. Archived from the original (PDF) on May 23, 2006.
- ^ Cite error: The named reference
:2was invoked but never defined (see the help page). - ^ Cite error: The named reference
deorbitwas invoked but never defined (see the help page). - ^ a b c Hansen, James (March 12, 2013). Spaceflight Revolution: NASA Langley Research Center from Sputnik to Apollo. Cia Publishing.