Polar

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General

Designation	23802 / 96013A
Launch date	24 Feb 1996 at 11:24 UT
Country of origin	United States
Operator	NASA
Mission	Scientific: magnetosphere study (auroral plasma physics)
Perigee/Apogee
Inclination	86°
Period
Launch vehicle	Delta 2 #33

Launched under the MELVS contract (Medium Expendable Launch Vehicle Services, between NASA and McDonnell Douglas)

Polar is one of two spacecraft in NASA's Global Geospace Science (GGS) mission, which is part of the International Solar-Terrestrial Physics program. Polar and a sister spacecraft, Wind 1, will perform simultaneous, coordinated measurements of key regions of Earth's space environment. Included are observations of the entry and transport of solar plasma over Earth's magnetic poles, imaging of the northern aurora (Northern Lights), and investigations of solar wind properties. Polar was built by Lockheed Martin Astro Space.

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End of life

Out of service	29 Apr 2008
Cause	decommissioned
Decay

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External resources

http://ggsfot.gsfc.nasa.gov/words/polar.html

http://uss-enterprise.bu.edu/BUSPACE/POLAR/polar.html
sat-index articles

Technical data

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Polar carries two booms and 6 long wire antennae. In the 'equatorial' plane of the satellite are a pair of antennae spanning 130 meters and, at right angles, another pair of antennae spanning 100 meters. Along the spin axis of the satellite are another pair of antennae with a span of 14 meters. These antennae are used to study electric and magnetic fields for the PWI (Plasma Wave Investigation) and EFI (Electric Field Instrument) experiments. Two larger but shorter (6 m long) booms carry more PWI instruments and the MFE (Magnetic Field Experiment).

Other instruments:
TIMAS (Toroidal Imaging Mass-Angle Spectrograph) to study fluxes of ions as a function of direction
TIDE (Thermal Ion Dynamics Experiment) and PSI (Plasma Source Instrument) which study connections between the polar ionosphere and the magnetotail
VIS (Visible Imaging System) and UVI (Ultraviolet Imager) which measure auroral emissions.
PIXIE (Polar Ionospheric X-ray Imaging Experiment) studies X-rays produced by energetic electrons in the upper atmosphere.
CAMMICE (Charge and Mass Magnetospheric Ion Composition Experiment) studies the isotopic composition of energetic ions.
CEPPAD (Comprehensive Energetic Particle Pitch Angle Distribution) studies high energy protons and electrons.
(JSR)

Telemetry: 2265.0 MHz (realtime: 55.6 kbps, playback: 512 kbps)
Command: 2085.688 MHz

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