Explorer 15 was launched on 27 October 1962, at Cape Canaveral Air Force Station, Florida, United States, with a Thor-Delta A .

Explorer 15 was a spin-stabilized, solar cell-powered spacecraft instrumented to study the artificial radiation belt produced by the Starfish high-altitude nuclear burst of July 1962.

[1] The instrumentation included three sets of particle detectors to study both electrons and protons, and a two-axis fluxgate magnetometers to determine magnetic aspect.

During ground processing of the telemetered data, the analog information was digitized with an accuracy of 1/100 of full scale.

One analog channel was subcommutated in a pattern 16 frames long and was used to telemeter spacecraft temperatures, power system voltages, electric currents, etc.

Counting rates from the two discrimination levels of this detector yielded information on directional fluxes of electrons with energies above 0.5 MeV.

[5] Six diffused silicon p-n junction semiconductor diodes were used to measure the energy spectrum of electrons and protons in the artificial radiation belt.

The detectors were operated in high and low bias modes, enabling discrimination of protons from electrons.

[7] This experiment was designed to measure the directional fluxes and spectra of low-energy trapped and auroral protons and electrons.

The energy fluxes of electrons in three ranges were measured separately using scatter geometry, absorbers, and the phototube current.