December 22 marks the 45th anniversary of the launch of the country's first serial geostationary satellite. Called Raduga (which means "rainbow" in Russian), the satellite was designed and built by ISS-Reshetnev Company.
Raduga inaugurated a new era of use of the geostationary orbit by the Russian space industry. Without any doubt, today this orbit is the most popular and common used one for satellite communications. The satellite embodied a great number of technical solutions that were pioneering at that time and hadn't been previously used in the neither domestic nor global satellite building industry. The design and layout of Raduga truly set the standard and later would be employed by the majority of satellites worldwide.
The satellite was the first to feature voltage stabilization that helped to boost the characteristics of the onboard power subsystem by 20 %. Raduga was also designed for three-axis stabilization with autonomous orientation of its solar panels that ensured constant rotation of the wings at a speed equal to the orbital one. ISS-Reshetnev Company was the first to introduce such a Sun tracking function, later it would become widespread globally.
When working on Raduga, ISS-Reshetnev Company substantially improved the variety and efficiency of ground tests the satellite had to undergo. It resulted in the increased active lifespan of the satellite – three years instead of one. In their turn, satellites of this series confirmed their reliability providing high-quality communications and broadcasting services even beyond their designed mission duration.
The development of the geostationary satellite technology made it possible to provide telecommunications services in almost every part of a large country and helped ISS-Reshetnev Company gain international recognition. Today, ISS-Reshetnev Company still remains Russia's key manufacturer of geostationary satellites.
The geostationary orbit is a circular geosynchronous orbit directly over the equator at an altitude of about 36 000 kilometers. The high orbit allows the satellites' orbital speed to match the rotation speed of Earth. Owing to this satellites remain essentially stable over the same spot. And just one satellite is enough to continuously cover almost half of the Earth's surface.