Vanguard 1

Vanguard 1
A model of Vanguard 1
NamesVanguard TV-4
Vanguard Test Vehicle-Four
Mission typeEarth science
OperatorNaval Research Laboratory
Harvard designation1958-Beta 2 [1]
COSPAR ID1958-002B Edit this at Wikidata
SATCAT no.00005
Mission duration90 days (planned)
66 years, 7 months and 17 days
(in orbit)
Spacecraft properties
SpacecraftVanguard 1
Spacecraft typeVanguard
ManufacturerNaval Research Laboratory
Launch mass1.46 kg (3.2 lb)
Dimensions152 mm (6.0 in) diameter, 3.0 ft (0.91 m) antenna span
Start of mission
Launch date17 March 1958, 12:15:41 GMT
RocketVanguard TV-4
Launch siteCape Canaveral, LC-18A
ContractorGlenn L. Martin Company
End of mission
Last contactMay 1964
Decay date2198 (estimated)
~ 240 years orbital lifetime [1]
Orbital parameters
Reference systemGeocentric orbit[2]
RegimeMedium Earth orbit
Perigee altitude654 km (406 mi)
Apogee altitude3,969 km (2,466 mi)
Inclination34.25°
Period134.27 minutes

Vanguard 1 (Harvard designation: 1958-Beta 2,[3] COSPAR ID: 1958-002B[1]) is an American satellite that was the fourth artificial Earth-orbiting satellite to be successfully launched, following Sputnik 1, Sputnik 2, and Explorer 1. It was launched 17 March 1958. Vanguard 1 was the first satellite to have solar electric power.[4] Although communications with the satellite were lost in 1964, it remains the oldest human-made object still in orbit, together with the upper stage of its launch vehicle.[1]

Vanguard 1 was designed to test the launch capabilities of a three-stage launch vehicle as a part of Project Vanguard, and the effects of the space environment on a satellite and its systems in Earth orbit. It also was used to obtain geodetic measurements through orbit analysis.[5] Vanguard 1, being small and light enough to carry with one hand, was described by the Soviet Premier, Nikita Khrushchev, as "the grapefruit satellite".[6]

  1. ^ a b c d "Display: Vanguard 1 1958-002B". NASA. 14 May 2020. Retrieved 1 February 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  2. ^ "Vanguard 1 Satellite details 1958-002B NORAD 00005". N2YO. Retrieved 1 February 2021.
  3. ^ "U.S. Space Objects Registry". Archived from the original on 6 October 2013. Retrieved 25 June 2009. Public Domain This article incorporates text from this source, which is in the public domain.
  4. ^ "Vanguard I The World's Oldest Satellite Still in Orbit". Archived from the original on 21 March 2015. Retrieved 24 September 2007. Public Domain This article incorporates text from this source, which is in the public domain.
  5. ^ O'Keefe, J. A.; Eckeis, Ann; Squires, R. K. (1959). "Vanguard Measurements Give Pear-Shaped Component of Earth's Figure". Science. 129 (3348): 565–566. doi:10.1126/science.129.3348.565.
  6. ^ "Vanguard I – The World's Oldest Satellite Still in Orbit". Spacecraft Engineering Department, U.S. Navy. Archived from the original on 19 September 2008. Public Domain This article incorporates text from this source, which is in the public domain.