25-MAY-1966 :- Explorer 32 satelite launched.

Explorer 32
also known as Atmosphere Explorer-B (AE-B), was a satellite launched by the United States to study the Earth's upper atmosphere. It was launched from Cape Canaveral on a Delta-C1 rocket, on May 25, 1966. It was the second of five Atmosphere Explorers, the first being Explorer 17.

Explorer 32 was designed to directly measure the temperature, composition, density, and pressure of the upper atmosphere.

The ion mass spectrometers measured the concentrations of different types of ions in the topside ionosphere, principally atomic hydrogen, helium, nitrogen, and oxygen. The concentrations were recorded as a function of time, location, and solar and geomagnetic activity. The satellite was able to perform a global study of the diurnal variation of the atmosphere during nearly two complete diurnal cycles, since the orbit plane processed one revolution each 5.5 months. The data from the ion mass spectrometers allowed for studies of: 

(1) the diurnal and seasonal variation of atmospheric ion composition, 

(2) the effect of atmospheric winds on the atomic hydrogen-atomic oxygen ion transition level, 

(3) the density and temporal variation of thermospheric atomic hydrogen, and 

(4) the altitude variation of ion composition in the midlatitude trough region.

The three magnetron density gauges measured the density of the neutral atmosphere as a function of altitude, time, latitude, and solar and geomagnetic activity.

The electron temperature and density instrument measure the distribution of electron temperatures and densities using a swept voltage electron probe.

The two neutral particle magnetic mass spectrometers were intended to measure the composition of the neutral atmosphere at altitudes between 285 and 1,000 kilometres (935,000 and 3,281,000 ft). One spectrometer failed after 4 days, and the other failed after 7 days in orbit.

The satellite drag atmospheric density experiment measured the density of the upper atmosphere as a function of altitude, latitude, season, and solar activity. The experiment was possible due to the symmetrical shape of Explorer 32. When the satellite was near perigee, it was observed by networks of ground-based Baker-Nunn cameras, as well as being tracked by radio and radar. Sequences of these observations were used to deduce the density of the atmosphere that the satellite was passing through.