Trumpet signal intelligence satellites were launched by Titan-4(01)A Centaur-T into highly elliptic Molniya-type orbits. In their elliptical orbits they would move very slowly over the northern hemisphere for most of their orbital period, allowing interception of microwave line-of-sight communications beams. Since they would move slowly through the beams during their orbit, a constellation of such satellites was required to monitor Soviet communications throughout the day.
Elliptical OrbitSTEP 0 (Space Test Experiment Platform 0) was a technology demonstration satellite flown under the Space Test Program (STP). DARPASAT (Defense Advanced Research Projects Agency Satellite) was designed to demonstrate advanced technology. Ball Aerospace designed, fabricated, integrated, and tested the spacecraft bus, and integrated two government-supplied payloads.
Low Earth Orbit