Pioneer 6, 7, 8, and 9 were space probes in the Pioneer program, launched between 1965 and 1969. They were a series of solar-orbiting, spin-stabilized, solar cell- and battery-powered satellites designed to obtain measurements on a continuing basis of interplanetary phenomena from widely separated points in space. They were also known as Pioneer A, B, C, and D. The fifth was lost in a launch accident, and therefore did not receive a numerical designation.
Explorer 35,, was a spin-stabilized spacecraft built by NASA as part of the Explorer program. Designed for the study of the interplanetary plasma, magnetic field, energetic particles, and solar X-rays, from lunar orbit.
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 18, also called IMP-A, IMP-1, Interplanetary Monitoring Platform-1 and S-74, was a NASA satellite launched as part of the Explorer program. Explorer 18 was launched on 27 November 1963 from Cape Canaveral Air Force Station (CCAFS), Florida, with a Thor-Delta C launch vehicle. Explorer 18 was the first satellite of the Interplanetary Monitoring Platform (IMP). Explorer 21 (IMP-B) launched in October 1964 and Explorer 28 (IMP-C) launched in May 1965 also used the same general spacecraft design.
SOLRAD 4B was a solar X-ray, ultraviolet, and electronic surveillance satellite. Developed by the United States Navy's United States Naval Research Laboratory, it was the fifth in both the SOLRAD and the GRAB programs.
Explorer 14, also called EPE-B or Energetic Particles Explorer-B, was a NASA spacecraft instrumented to measure cosmic-ray particles, trapped particles, solar wind protons, and magnetospheric and interplanetary magnetic fields. It was the second of the S-3 series of spacecraft, which also included Explorer 12, 14, 15, and 26. It was launched on 2 October 1962, aboard a Thor-Delta launch vehicle.
Student Nitric Oxide Explorer, was a NASA small scientific satellite which studied the concentration of nitric oxide in the thermosphere. It was launched in 1998 as part of NASA's Explorer program. The satellite was the first of three missions developed within the Student Explorer Demonstration Initiative (STEDI) program funded by the NASA and managed by the Universities Space Research Association (USRA). STEDI was a pilot program to demonstrate that high-quality space science can be carried out with small, low-cost free-flying satellites on a time scale of two years from go-ahead to launch. The satellite was developed by the University of Colorado Boulder's Laboratory for Atmospheric and Space Physics (LASP) and had met its goals by the time its mission ended with reentry in December 2003.
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 28, also called IMP-C, IMP-3 and Interplanetary Monitoring Platform-3, was a NASA satellite launched on 29 May 1965 to study space physics, and was the third spacecraft launched in the Interplanetary Monitoring Platform program. It was powered by chemical batteries and solar panels. There were 7 experiments on board, all devoted to particle studies. Performance was normal until late April 1967, when intermittent problems began. It stayed in contact until 12 May 1967, when contact was lost. The orbit decayed until it re-entered the atmosphere on 4 July 1968. The spacecraft design was similar to its predecessors Explorer 18 (IMP-A), launched in November 1963, and Explorer 21 (IMP-B), launched in October 1964, though this satellite was a few kilograms lighter. The successor Explorer 33 (IMP-D) began the use of a new design.
Explorer 15, also called EPE-C or Energetic Particles Explorer-C, was a NASA satellite launched as part of the Explorer program. Explorer 15 was launched on 27 October 1962, at Cape Canaveral Air Force Station, Florida, United States, with a Thor-Delta A.
Explorer 21, also called IMP-B, IMP-2 and Interplanetary Monitoring Platform-2, was a NASA satellite launched as part of Explorer program. Explorer 21 was launched on 4 October 1964, at 03:45:00 GMT from Cape Canaveral (CCAFS), Florida, with a Thor-Delta C launch vehicle. Explorer 21 was the second satellite of the Interplanetary Monitoring Platform, and used the same general design as its predecessor, Explorer 18 (IMP-A), launched the previous year, in November 1963. The following Explorer 28 (IMP-C), launched in May 1965, also used a similar design.
Solrad 9, also known Explorer 37 and Explorer SE-B, was one of the SOLRAD program that began in 1960 to provide continuous coverage of solar radiation with a set of standard photometers.
Solrad 10, also known Explorer 44, NRL-PL 165 and Explorer SE-C, was one of the SOLRAD series designed to provide continuous coverage of wavelength and intensity changes in solar radiation in the UV, soft and hard X-ray regions. The satellite also mapped the celestial sphere using a high-sensitivity X-ray detector. Information collected was expected to contribute to a better understanding of the physical processes involved in solar flares and other solar activity, and the potential effects of this activity on short-wave communications, as well as on future human space travel. For the period of July 1971 to June 1973, the core memory data of Explorer 44 were used rather than those from Explorer 37. The Explorer 44 core memory failed on 11 June 1973, and Explorer 37 was heavily used until 25 February 1974, when the gas supply of the attitude control system was exhausted.
Explorer 50, also known as IMP-J or IMP-8, was a NASA satellite launched to study the magnetosphere. It was the eighth and last in a series of the Interplanetary Monitoring Platform.
SOLRAD 7A was the seventh solar X-ray monitoring satellite in the SOLRAD series, and the fourth to successfully orbit the Earth. It was boosted into orbit along with four other military satellites atop a Thor Augmented Delta-Agena D rocket on January 11, 1964. Data returned by SOLRAD 7A dramatically revised scientific models of the solar corona.
SOLRAD1 is the public designation for SOLRAD/GRAB 1, a combination science and surveillance satellite launched into orbit on 22 June 1960. It was the first satellite to successfully observe solar X-rays, the first to conduct surveillance from orbit, and the first to be launched with another instrumented satellite.
SOLRAD 2 was the public designation for a combination surveillance and solar X-rays and ultraviolet scientific satellite, the second in the SOLRAD program developed by the United States Navy's Naval Research Laboratory. The SOLRAD scientific package aboard the satellite provided cover for the GRAB electronic surveillance package, the mission of which was to map the Soviet Union's air defense radar network.
SOLRAD 3 was a solar X-ray satellite, the third in the SOLRAD program. Developed by the United States Navy's Naval Research Laboratory (USNRL), it shared satellite space with and provided cover for the Navy's GRAB 2, a secret electronic surveillance program.
SOLRAD 4 was a solar X-rays, ultraviolet, and electronic surveillance satellite. Developed by the United States Navy's United States Naval Research Laboratory (USNRL), it was the fourth in both the SOLRAD and the GRAB programs.
