CRRES
Encyclopedia
The Combined Release and Radiation Effects Satellite (CRRES) was launched on July 25, 1990 into a geosynchronous transfer orbit (GTO) for a nominal three-year mission to investigate fields, plasmas
, and energetic particles inside the Earth's magnetosphere
. As part of the CRRES program, the SPACERAD (Space Radiation Effects) project, managed by Air Force Geophysics Laboratory, investigated the radiation environment of the inner and outer radiation belts and measured radiation effects on state-of-the-art microelectronics devices. Other magnetospheric, ionospheric
, and cosmic ray
experiments were also included onboard CRRES and supported by NASA
or the Office of Naval Research. The chemical release project was managed by NASA/MSFC and utilized the release of chemicals from onboard canisters at low altitudes near dawn and dusk perigee times and at high altitudes near local midnight. The chemical releases were monitored with optical and radar instrumentation by ground-based observers to measure the bulk properties and movement of the expanding clouds of photo-ionized plasma along field lines after the releases occurred. In order to study the magnetosphere at different local times during the mission, the satellite orbit was designed to precess with respect to the earth-sun line such that the local time at apogee decreased by 2.5 minutes/day from 08:00 (LT) just after launch and returned to this position in nineteen month cycles. The CRRES spacecraft had the shape of an octagonal prism
with solar arrays on the top side. The prism is 1 m high and 3 m between opposite faces. Four of the eight compartments were for the chemical canisters and the other four housed the SPACERAD and other experiments. The spacecraft body was spun at 2.2 rpm about a spin axis in the ecliptic plane and kept pointed about 12 degrees ahead of the Sun's apparent motion in celestial coordinates. Pre-launch and in-flight operations were supported by the Space Test and Transportation Program Office of the U.S. Air Force Space Division. Contact with the CRRES spacecraft was lost on October 12, 1991 and was presumed to be due to onboard battery failure.
Taken From Nasa.
Plasma (physics)
In physics and chemistry, plasma is a state of matter similar to gas in which a certain portion of the particles are ionized. Heating a gas may ionize its molecules or atoms , thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions...
, and energetic particles inside the Earth's magnetosphere
Magnetosphere
A magnetosphere is formed when a stream of charged particles, such as the solar wind, interacts with and is deflected by the intrinsic magnetic field of a planet or similar body. Earth is surrounded by a magnetosphere, as are the other planets with intrinsic magnetic fields: Mercury, Jupiter,...
. As part of the CRRES program, the SPACERAD (Space Radiation Effects) project, managed by Air Force Geophysics Laboratory, investigated the radiation environment of the inner and outer radiation belts and measured radiation effects on state-of-the-art microelectronics devices. Other magnetospheric, ionospheric
Ionosphere
The ionosphere is a part of the upper atmosphere, comprising portions of the mesosphere, thermosphere and exosphere, distinguished because it is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere...
, and cosmic ray
Cosmic ray
Cosmic rays are energetic charged subatomic particles, originating from outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. The term ray is historical as cosmic rays were thought to be electromagnetic radiation...
experiments were also included onboard CRRES and supported by NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
or the Office of Naval Research. The chemical release project was managed by NASA/MSFC and utilized the release of chemicals from onboard canisters at low altitudes near dawn and dusk perigee times and at high altitudes near local midnight. The chemical releases were monitored with optical and radar instrumentation by ground-based observers to measure the bulk properties and movement of the expanding clouds of photo-ionized plasma along field lines after the releases occurred. In order to study the magnetosphere at different local times during the mission, the satellite orbit was designed to precess with respect to the earth-sun line such that the local time at apogee decreased by 2.5 minutes/day from 08:00 (LT) just after launch and returned to this position in nineteen month cycles. The CRRES spacecraft had the shape of an octagonal prism
Prism (geometry)
In geometry, a prism is a polyhedron with an n-sided polygonal base, a translated copy , and n other faces joining corresponding sides of the two bases. All cross-sections parallel to the base faces are the same. Prisms are named for their base, so a prism with a pentagonal base is called a...
with solar arrays on the top side. The prism is 1 m high and 3 m between opposite faces. Four of the eight compartments were for the chemical canisters and the other four housed the SPACERAD and other experiments. The spacecraft body was spun at 2.2 rpm about a spin axis in the ecliptic plane and kept pointed about 12 degrees ahead of the Sun's apparent motion in celestial coordinates. Pre-launch and in-flight operations were supported by the Space Test and Transportation Program Office of the U.S. Air Force Space Division. Contact with the CRRES spacecraft was lost on October 12, 1991 and was presumed to be due to onboard battery failure.
Taken From Nasa.