Key facts
- Names
- Vanguard TV-4, Vanguard Test Vehicle-Four
- Mission type
- Earth science
- Operator
- Naval Research Laboratory
- Harvard designation
- 1958-Beta 2
- Cospar id
- 1958-002B
- Satcat number span no
- 00005
- Mission duration
- 90 days (planned) , 68 years, 2 months and 18 days , (in orbit)
- Spacecraft
- Vanguard 1
- Spacecraft type
- Vanguard
- Manufacturer
- Naval Research Laboratory
- Launch mass
- 1.46 kg (3.2 lb)
- Dimensions
- 152 mm (6.0 in) diameter, 3.0 ft (0.91 m) antenna span
- Launch date
- 17 March 1958, 12:15:41 GMT
- Rocket
- Vanguard TV-4
- Launch site
- Cape Canaveral , LC-18A
- Contractor
- Glenn L. Martin Company
- Last contact
- May 1964
- Decay date
- 2198 (estimated), ~ 240 years orbital lifetime
via Wikipedia infobox
Wikidata facts
- Duration
- 2200
- Diameter
- 16.5
- Mass
- 1.46
- Orbital period
- 132.8
- Image
- Vanguard 1.jpg
Show 11 more facts
- semi-major axis of an orbit
- 8620
- orbital eccentricity
- 0.1844061
- Commons category
- Vanguard I
- UTC date of spacecraft launch
- 1958-03-17
- service retirement
- 1964-05-00
- periapsis
- 658.9
- apoapsis
- 3839.9
- orbital inclination
- 34.2
- longitude of ascending node
- 181.84
- argument of periapsis
- 120.16
- mean anomaly
- 10.84
via Wikidata · CC0
~8 min read
Article
Vanguard 1 (Harvard designation: 1958-Beta 2, COSPAR ID: 1958-002B) 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. Although communications with the satellite were lost in 1964, it remains the oldest artificial object still in orbit, together with the upper stage of its launch vehicle.
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. Vanguard 1, being small and light enough to carry with one hand, was described by the Soviet Premier, Nikita Khrushchev, as "the grapefruit satellite".