Thursday, July 19, 2012
Happy 45th, Explorer 35!
This Thursday, July 19th, marks the 45th anniversary of the launch of NASA's lunar orbiter, Explorer 35 (IMP-E). Explorer 35 was the eighth lunar orbiter mission launched from Earth and the fifth launched by the United States. Unlike the U.S. Lunar Orbiter missions, which performed photo reconnaissance to prepare for U.S. human landings on the moon, the focus of the Explorer 35 mission was interplanetary study. Its mission disciplines included planetary science, solar physics and space physics.
The Explorer 35 spacecraft was spin-stabilized and instrumented for interplanetary studies, at lunar distances, of the interplanetary plasma, magnetic field, energetic particles, and solar X-rays. The spacecraft was launched into an elliptical lunar orbit. The spin axis direction was nearly perpendicular to the ecliptic plane, and the spin rate was 25.6 rpm. Explorer 35 achieved all of its mission objectives and, after successful operation for 6 years, was turned off on June 24, 1973.