Thirty years ago today — August 3, 1981 — a Delta rocket out of Vandenberg AFB placed two satellites in orbit for a unique interactive mission.
(DE-1 image of an aurora over North America, taken with the University of Iowa’s Spin-Scan Auroral Imager. NASA image.)
Dynamics Explorer 1 and Dynamics Explorer 2 were high- and low-altitude spacecraft, respectively, intended to
investigate the strong interactive processes coupling the hot, tenuous, convecting plasmas of the magnetosphere and the cooler, denser plasmas and gases corotating in the earth’s ionosphere, upper atmosphere, and plasmasphere.
The spacecrafts’ orbits were such that one made high-altitude observations while the other made low-altitude observations, which could be compared to better understand atmospheric dynamics and the interaction of our atmosphere with charged particles from the Sun. Mission operations ended in 1991.
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