The Dynamics Explorer (DE) mission's general objective is 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. Two satellites, DE 1 and DE 2, were launched together and were placed in polar coplanar orbits, permitting simultaneous measurements at high and low altitudes in the same field-line region. The DE 1 spacecraft (high-altitude mission) uses an elliptical orbit selected to allow measurements extending from the hot magnetospheric plasma through the plasmasphere to the cool ionosphere; global auroral imaging, wave measurements in the heart of the magnetosphere, and crossing of auroral field lines at several earth radii; and measurements for significant periods along a magnetic field flux tube.
Dynamics Explorer 1 science operations were terminated on October 22, 1990, on February 28, 1991 operations were officially terminated.
Dynamics Explorer 2 reentered the atmosphere on February 19, 1983.