The satellite design provided an economical and stable Sun-synchronous platform for advanced operational instruments to measure the atmosphere of Earth, its surface and cloud cover, and the near-space environment.

[4] Primary sensors included: 1) an Advanced very-high-resolution radiometer (AVHRR/2) for global cloud cover observations, 2) a TIROS Operational Vertical Sounder (TOVS) suite for atmospheric temperature and water profiling.

[4] The AVHRR/2 was a four-channel scanning radiometer capable of providing global daytime and nighttime sea-surface temperature and information about ice, snow, and clouds.

All three instruments were designed to determine radiances needed to calculate temperature and humidity profiles of the atmosphere from the surface to the stratosphere (approximately 1 mb).

It has three channels that operate at 15.0 μm with three pressure-modulated cells containing CO2 to accomplish selective bandpass filtration of the sampled radiance.

The third instrument, the MSU, has four channels operating in the 50- to 60-GHz oxygen band (50.31, 53.73, 54.96 and 57.95 GHz) to obtain temperature profiles which are free of cloud interference.

The system receives low-duty-cycle transmissions of meteorological observations from free-floating balloons, ocean buoys, other satellites, and fixed ground-based sensor platforms distributed around the globe.

[7] The Search and Rescue Satellite Aided Tracking (SARSAT) instruments had the capability of detecting and locating existing emergency transmitters in a manner independent of the environmental data.

The 406-MHz data were also processed by the Search and Rescue Processor (SARP) and retransmitted in real time and stored on the spacecraft for later transmittal to the CDA stations in Alaska and Virginia, thus providing full global coverage.

The SBUV/2 instrument measured backscattered solar radiation in an 11.3° field of view in the nadir direction at 12 discrete, 1.1-nm wide, wavelength bands between 252.0 and 339.8 nm.

The SBUV/2 had another narrowband filter photometer channel, called the Cloud Cover Radiometer (CCR), which continuously measured the surface of Earth brightness at 380 nm.