Orbiting Geophysical Observatory

Orbiting Geophysical Observatory (OGO), any of a series of six unmanned scientific satellites launched by the United States from 1964 to 1969. Equipped with a complex of magnetometers, these orbiting satellites were designed to study the Earth’s magnetosphere (i.e., zone of strong magnetic forces around the planet) and its effect on high-energy particles emitted by the Sun. These studies included investigations of auroral displays, magnetic storms, and other related phenomena. OGO-1, the first in the...