Launched in 1969, just a few months after humans first set foot on the Moon, Skynet-1A was put high above Africa’s east coast to relay communications for British forces. When the spacecraft ceased working a few years later, gravity might have been expected to pull it even further to the east, out over the Indian Ocean. But today, curiously, Skynet-1A is actually half a planet away, in a position 22,369 miles (36,000km) above the Americas. Orbital mechanics mean it’s unlikely the half-tonne military spacecraft simply drifted to its current location. Almost certainly, it was commanded to fire its thrusters in the mid-1970s to take it westwards. The question is who that was and with what authority and purpose?…

You might also reasonably ask why it still matters. After all, we’re talking about some discarded space junk from 50 years ago…No matter how Skynet-1A  got shifted to its present position, it was ultimately allowed to die in an awkward place when really it should have been put in an “orbital graveyard“. This refers to a region even higher in the sky where old space junk runs zero risk of running into active telecommunications satellites. Graveyarding is now standard practice, but back in the 1970s no-one gave much thought to space sustainability.

Attitudes have since changed because the space domain is getting congested and  collisions between defunct satellites  generate large amounts of space debris or space junk…”We need to avoid…super-spreader events. When these things explode or something collides with them, it generates thousands of pieces of debris that then become a hazard to something else that we care about.”

Excerpt from Jonathan Amos, Somebody moved UK’s oldest satellite, and no-one knows who or why, Science, Nov. 8, 2024