Fifteen years ago today — February 24, 1996 — a Delta-II rocket out of Vandenberg AFB lifted a spacecraft simply named “Polar” into a polar orbit.
(Diagram of the Polar spacecraft. See text below for acronyms. NASA image.)
Polar was one of several spacecraft in the International Solar Terrestrial Physics Project. (Here is a better project overview site.) Together with “Wind” and “Geotail,” Polar’s mission was to “obtain coordinated, simultaneous investigations of the Sun-Earth space environment over an extended period of time.”
Polar operations ended in April 2008.
In the image above, the labels point out different instruments on the spacecraft:
- CAMMICE = Charge and Mass Magnetospheric Ion Composition Experiment
- CEPPAD = Comprehensive Energetic-Particle Pitch-Angle Distribution
- EFI = Electric Fields Investigation
- HYDRA = Hot Plasma Analyzer
- MFG (should be MFE?) = Magnetic Fields Experiment
- PIXIE = Polar Ionospheric X-ray Imaging Experiment
- PWI = Plasma Waves Investigation
- SEPS = Source/Loss Cone Energetic Particle Spectrometer
- TIDE = Thermal Ion Dynamics Experiment
- TIMAS = Toroidal Imaging Mass-Angle Spectrograph
- VIS = Visible Imaging System
- UVI = Ultraviolet Imager
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