COSMOS 644, a 1974 Soviet Satellite, Continues to Orbit as Tracked Debris
COSMOS 644, a 60 kg Soviet Strela-1M relay satellite launched on April 23, 1974, from Plesetsk, remains in orbit more than 52 years later. This military communications satellite, one of eight Strela-1M spacecraft launched together, circles Earth approximately 12.6 times a day in a 1,336 x 1,490 km corridor. Although it ceased functioning decades ago, its orbit is stable enough for the Space Surveillance Network to track it under NORAD catalog number 7268. The Strela-1M system was the Soviet Union’s first operational store-and-dump tactical communications network, designed to allow ground stations to upload messages during one pass and download them on the next. COSMOS 644 was the fourth satellite in Block 09 of this program. Its operational lifetime was approximately six months, typical for Strela-1M units whose batteries and electronics were not designed for long service. After its mission ended, it became part of the growing population of debris objects in the 1,400 km altitude band.
