[3] The spin-stabilized satellite's external structure consisted of two truncated conical fiberglass shells joined by a cylindrical aluminum center section.

Additional power was provided by 15 rechargeable nickel-cadmium batteries that were positioned on its equator near the outer skin as an aid in maintaining a proper spin rate.

[6] The solar X-ray and Lyman-alpha radiation were measured by means of gas ionization chambers mounted on opposite sides of the upper portion of the double cone configuration of the Explorer 7 satellite.

Intensities were monitored in order to obtain a long-term history of solar X-ray and Lyman-alpha fluxes and to correlate these with terrestrial atmospheric responses.

The Lyman-alpha detectors (on the opposite side), which were circular ionization chambers (1.9 cm (0.75 in) in diameter) filled with nitric oxide gas, had lithium fluoride windows.

The primary instrumentation consisted of five bolometers in the form of hollow silver hemispheres that were thermally insulated from, but in close proximity to specially aluminized mirrors.

[8] Significantly, it also carried Dr. Verner E. Suomi's flat-plate radiometer, improved with the help of Robert Parent, that took the first Earth radiation budget measurements from space and initiated the era of satellite studies of the climate.

[9] Using both satellite observations of the Earth's heat balance and atmospheric cooling rates measured by net flux radiosondes, Suomi established the important role played by clouds in absorbing radiated solar energy.

These observations established that Earth's energy budget varies markedly due to the effect of clouds, the surface albedo, and other absorbing constituents.

Using these instruments, Suomi and his team discovered that the Earth absorbed more of the Sun's energy than originally thought and demonstrated that it was possible to measure and quantify seasonal changes in the global heat budget.

[10] Two omnidirectional Geiger counters (Anton 302 and 112) were used to conduct a comprehensive spatial and temporal monitoring of total cosmic-ray intensity, geomagnetically trapped corpuscular radiation, and solar protons.

On 16 June 1960, NASA announced one of the four frequency modulated subcarriers on the second transmitter had become erratic and the information it was transmitting on 3 of the 7 experiments was no longer intelligible.

The spacecraft provided significant geophysical information on radiation and magnetic storms, demonstrated methods of controlling internal temperatures, recorded the first micrometeorite penetration of a sensor in flight, and detected large scale weather patterns.