The ionosphere is the ionized part of the upper atmosphere of Earth, from about 48 km (30 mi) to 965 km (600 mi) above sea level, a region that includes the thermosphere and parts of the mesosphere and exosphere. The ionosphere is ionized by solar radiation. It plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere. It has practical importance because, among other functions, it influences radio propagation to distant places on Earth.
The Pioneer Venus project was part of the Pioneer program consisting of two spacecraft, the Pioneer Venus Orbiter and the Pioneer Venus Multiprobe, launched to Venus in 1978. The program was managed by NASA's Ames Research Center.
Nozomi was a Mars orbiter that failed to reach Mars due to electrical failures. The mission was terminated on December 31, 2003.
Mars 96 was a failed Mars mission launched in 1996 to investigate Mars by the Russian Space Forces and not directly related to the Soviet Mars probe program of the same name. After failure of the second fourth-stage burn, the probe assembly re-entered the Earth's atmosphere, breaking up over a 320 km (200 mi) long portion of the Pacific Ocean, Chile, and Bolivia. The Mars 96 spacecraft was based on the Phobos probes launched to Mars in 1988. They were of a new design at the time and both ultimately failed. For the Mars 96 mission the designers believed they had corrected the flaws of the Phobos probes, but the value of their improvements was never demonstrated due to the destruction of the probe during the launch phase.
IMAGE is a NASA Medium Explorer mission that studied the global response of the Earth's magnetosphere to changes in the solar wind. It was believed lost but as of August 2018 might be recoverable. It was launched 25 March 2000, at 20:34:43.929 UTC, by a Delta II launch vehicle from Vandenberg Air Force Base on a two-year mission. Almost six years later, it unexpectedly ceased operations in December 2005 during its extended mission and was declared lost. The spacecraft was part of NASA's Sun-Earth Connections Program, and its data has been used in over 400 research articles published in peer-reviewed journals. It had special cameras that provided various breakthroughs in understanding the dynamics of plasma around the Earth. The principal investigator was Jim Burch of the Southwest Research Institute.
Explorer 32, also known as Atmosphere Explorer-B (AE-B), was a NASA satellite launched by the United States to study the Earth's upper atmosphere. It was launched from Cape Canaveral on a Delta C1 launch vehicle, on 25 May 1966. It was the second of five "Atmosphere Explorer", the first being Explorer 17. Though it was placed in a higher-than-expected orbit by a malfunctioning second stage on its launch vehicle, Explorer 32 returned data for ten months before failing due to a sudden depressurization. The satellite reentered the Earth's atmosphere on 22 February 1985.
The following is a chronology of discoveries concerning the magnetosphere.
The plasmasphere, or inner magnetosphere, is a region of the Earth's magnetosphere consisting of low-energy (cool) plasma. It is located above the ionosphere. The outer boundary of the plasmasphere is known as the plasmapause, which is defined by an order of magnitude drop in plasma density. In 1963 American scientist Don Carpenter and Soviet astronomer Konstantin Gringauz proved the plasmasphere and plasmapause's existence from the analysis of very low frequency (VLF) whistler wave data. Traditionally, the plasmasphere has been regarded as a well behaved cold plasma with particle motion dominated entirely by the geomagnetic field and, hence, co-rotating with the Earth.
Venera-D is a proposed Russian space mission to Venus that would include an orbiter and a lander to be launched in 2029. The orbiter's prime objective is to perform observations with the use of a radar. The lander, based on the Venera design, would be capable of operating for a long duration on the planet's surface. The "D" in Venera-D stands for "dolgozhivushaya," which means "long lasting" in Russian.
The magnetosphere of Jupiter is the cavity created in the solar wind by the planet's magnetic field. Extending up to seven million kilometers in the Sun's direction and almost to the orbit of Saturn in the opposite direction, Jupiter's magnetosphere is the largest and most powerful of any planetary magnetosphere in the Solar System, and by volume the largest known continuous structure in the Solar System after the heliosphere. Wider and flatter than the Earth's magnetosphere, Jupiter's is stronger by an order of magnitude, while its magnetic moment is roughly 18,000 times larger. The existence of Jupiter's magnetic field was first inferred from observations of radio emissions at the end of the 1950s and was directly observed by the Pioneer 10 spacecraft in 1973.
The Global Geospace Science (GGS) Polar satellite was a NASA science spacecraft designed to study the polar magnetosphere and aurorae. It was launched into orbit in February 1996, and continued operations until the program was terminated in April 2008. The spacecraft remains in orbit, though it is now inactive. Polar is the sister ship to GGS Wind.
C/NOFS, or Communications/Navigation Outage Forecasting System was a USAF satellite developed by the Air Force Research Laboratory (AFRL) Space Vehicles Directorate to investigate and forecast scintillations in the Earth's ionosphere. It was launched by an Orbital Sciences Corporation Pegasus-XL launch vehicle at 17:02:48 UTC on 16 April 2008 and decayed on 28 November 2015.
Explorer 54, also called as AE-D, was a NASA scientific satellite belonging to series Atmosphere Explorer, being launched on 6 October 1975 from Vandenberg Air Force Base board a Thor-Delta 2910 launch vehicle.
Energetic Neutral Atom (ENA) imaging, often described as "seeing with atoms", is a technology used to create global images of otherwise invisible phenomena in the magnetospheres of planets and throughout the heliosphere.
The ISEE-1 was an Explorer-class mother spacecraft, International Sun-Earth Explorer-1, was part of the mother/daughter/heliocentric mission. ISEE-1 was a 340.2 kg (750 lb) space probe used to study magnetic fields near the Earth. ISEE-1 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.
Explorer 51, also called as AE-C, was a NASA scientific satellite belonging to series Atmosphere Explorer, being launched on 16 December 1973, at 06:18:00 UTC, from Vandenberg board a Delta 1900 launch vehicle.
Explorer 55, also called as AE-E, was a NASA scientific satellite belonging to series Atmosphere Explorer, being launched on 20 November 1975 from Cape Canaveral Air Force Station (CCAFS) board a Thor-Delta 2910 launch vehicle.
AMPTE-Charge Composition Explorer, also called as AMPTE-CCE or Explorer 65, was a NASA satellite designed and tasked to study the magnetosphere of Earth, being launched as part of the Explorer program. The AMPTE mission was designed to study the access of solar wind ions to the magnetosphere, the convective-diffusive transport and energization of magnetospheric particles, and the interactions of plasmas in space.
Dynamics Explorer 1 was a NASA high-altitude mission, launched on 3 August 1981, and terminated on 28 February 1991. It consisted of two satellites, DE-1 and DE-2, whose purpose was to investigate the interactions between plasmas in the magnetosphere and those in the ionosphere. The two satellites were launched together into polar coplanar orbits, which allowed them to simultaneously observe the upper and lower parts of the atmosphere.
Dynamics Explorer 2 was a NASA low-altitude mission, launched on 3 August 1981. It consisted of two satellites, DE-1 and DE-2, whose purpose was to investigate the interactions between plasmas in the magnetosphere and those in the ionosphere. The two satellites were launched together into polar coplanar orbits, which allowed them to simultaneously observe the upper and lower parts of the atmosphere.
