Vanguard 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. 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.
Project Vanguard was a program managed by the United States Navy Naval Research Laboratory (NRL), which intended to launch the first artificial satellite into low Earth orbit using a Vanguard rocket. as the launch vehicle from Cape Canaveral Missile Annex, Florida.
Vanguard 2 is an Earth-orbiting satellite launched 17 February 1959 at 15:55:02 GMT, aboard a Vanguard SLV-4 rocket as part of the United States Navy's Project Vanguard. The satellite was designed to measure cloud cover distribution over the daylight portion of its orbit, for a period of 19 days, and to provide information on the density of the atmosphere for the lifetime of its orbit. As the first weather satellite and one of the first orbital space missions, the launch of Vanguard 2 was an important milestone in the Space Race between the United States and the Soviet Union. Vanguard 2 remains in orbit.
Explorer 35,, was a spin-stabilized spacecraft built by NASA as part of the Explorer program. It was designed for the study of the interplanetary plasma, magnetic field, energetic particles, and solar X-rays, from lunar orbit.
Explorer 6, or S-2, was a NASA satellite, launched on 7 August 1959, at 14:24:20 GMT. It was a small, spheroidal satellite designed to study trapped radiation of various energies, galactic cosmic rays, geomagnetism, radio propagation in the upper atmosphere, and the flux of micrometeorites. It also tested a scanning device designed for photographing the Earth's cloud cover. On 14 August 1959, Explorer 6 took the first photos of Earth from a satellite.
Explorer 7 was a NASA satellite launched on 13 October 1959, at 15:30:04 GMT, by a Juno II launch vehicle from Cape Canaveral Air Force Station (CCAFS) to an orbit of 573 × 1,073 km (356 × 667 mi) and inclination of 50.27°. It was designed to measure solar X-ray and Lyman-alpha flux, trapped energetic particles, and heavy primary cosmic rays. Secondary objectives included collecting data on micrometeoroid penetration, molecular sputtering and studying the Earth-atmosphere heat balance.
Explorer 8 was a NASA research satellite launched on 3 November 1960. It was intended to study the temporal and spatial distribution of the electron density, the electron temperature, the ion concentration, the ion mass, the micrometeorite distribution, and the micrometeorite mass in the ionosphere at altitudes between 400 km (250 mi) and 1,600 km (990 mi) and their variation from full sunlit conditions to full shadow, or nighttime, conditions.
Vanguard TV-3BU, also called Vanguard Test Vehicle-Three Backup, was the second flight of the American Vanguard rocket. An unsuccessful attempt to place an unnamed satellite, Vanguard 1B, into orbit, the rocket was launched on 5 February 1958. It was launched from LC-18A at the Cape Canaveral Air Force Station. Fifty-seven seconds after launch, control of the vehicle was lost, and it failed to achieve orbit. At 57 seconds, the booster suddenly pitched down. The skinny second stage broke in half from aerodynamic stress, causing the Vanguard to tumble end-over-end before a range safety officer sent the destruct command. The cause of the failure was attributed to a spurious guidance signal that caused the first stage to perform unintended pitch maneuvers. Vanguard TV-3BU only reached an altitude of 6.1 km (3.8 mi), the goal was 3,840 km (2,390 mi).
The ISEE-2 was an Explorer-class daughter spacecraft, International Sun-Earth Explorer-2, was part of the mother/daughter/heliocentric mission. ISEE-2 was a 165.78 kg (365.5 lb) space probe used to study magnetic fields near the Earth. ISEE-2 was a spin-stabilized spacecraft and based on the design of the prior IMP series of spacecraft. ISEE-1 and ISEE-2 were launched on 22 October 1977, and they re-entered on 26 September 1987.
Vanguard TV-5, also called Vanguard Test Vehicle-Five, was a failed flight of the American Vanguard rocket following the successful launch of Vanguard 1 on Vanguard TV-4. Vanguard TV-5 launched on 29 April 1958 at 02:53:00 GMT, from Launch Complex 18A at the Cape Canaveral Air Force Station. The rocket was unsuccessful in its attempt to place an unnamed satellite into orbit.
Vanguard SLV-1, also called Vanguard Satellite Launch Vehicle-1 was hoped to be the second successful flight of the American Vanguard rocket following the successful launch of the Vanguard 1 satellite on rocket Vanguard TV-4 in March 1958.
Vanguard SLV-3, also called Vanguard Satellite Launch Vehicle-3 hoped to be the second successful flight of the American Vanguard rocket following successful Vanguard 1 satellite on rocket Vanguard TV-4.
Vanguard SLV-5, also called Vanguard Satellite Launch Vehicle-Five hoped to be the third successful flight of the American Vanguard rocket following the successful Vanguard 2 satellite on rocket Vanguard SLV-4.
Vanguard SLV-6, also called Vanguard Satellite Launch Vehicle-Six, hoped to be the third successful flight of the American Vanguard rocket following the successful Vanguard 2 satellite on rocket Vanguard SLV-4. Vanguard Satellite Launch Vehicle-6 (SLV-6) was designed to carry a small spherical satellite into Earth orbit to study solar heating of Earth and the heat balance. A faulty second stage pressure valve caused a mission failure.
Explorer 12, also called EPE-A or Energetic Particles Explorer-A and as S3), was a NASA satellite built to measure the solar wind, cosmic rays, and the Earth's magnetic field. It was the first of the S-3 series of spacecraft, which also included Explorer 12, 14, 15, and 26. It was launched on 16 August 1961, aboard a Thor-Delta launch vehicle. It ceased transmitting on 6 December 1961 due to power failure.
Explorer 26 was a NASA satellite launched on 21 December 1964, as part of NASA's Explorer program. Its primary mission was to study the Earth's magnetic field.
Explorer S-1, also known as NASA S-1 or Explorer 7X, was a NASA Earth science satellite equipped with a suite of scientific instruments to study the environment around the Earth. The spacecraft and its Juno II launch vehicle were destroyed five seconds after launch on 16 July 1959, in a spectacular launch failure caused by complications with the launch vehicle's power supply. A relaunch of the mission in October 1959, Explorer 7 (S-1A), was successful.
Explorer 13,, was a NASA satellite launched as part of the Explorer program on 25 August 1961, at 18:29:44 GMT, from Wallops Flight Facility (WFF), Virginia.
Explorer 16, also called S-55B, was a NASA satellite launched as part of the Explorer program. Explorer 16 was launched on 16 December 1962, at 14:33:04 GMT, from Wallops Flight Facility, Virginia, with a Scout X-3.
Explorer 45 was a NASA satellite launched as part of Explorer program. Explorer 45 was the only one to be released from the program Small Scientific Satellite.
