Polar Bear

American earth magnetosphere satellite built by JHU/APL for USAF STP (Space Test Program), USA. Used Transit-Bus. One launch, 1986. Also known as STP P87-1, a military mission designed to study communications interference caused by solar flares and increased auroral activity.

Polar Beacon and Research satellite. The data from the mission complemented data taken by its predecessor, HILAT. The core vehicle was a Transit navigational satellite that was retrieved from the Smithsonian's National Air & Space Museum where it had been on display for 8 years. Spacecraft: Gravity gradient stabilized by deployable boom with tip mass.4 small deployable solar arrays. Payload: Auroral Imaging Remote Sensor imaged the aurora borealis; Beacon Experiment monitored ionospheric propagation over the poles.