10.11.2024

Someone moved the UK's oldest satellite and there appears to be no record of exactly who, when or why.

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?

It's intriguing that key information about a once vital national security asset can just evaporate. But, fascination aside, you might also reasonably ask why it still matters. After all, we're talking about some discarded space junk from 50 years ago.

"It's still relevant because whoever did move Skynet-1A did us few favours," says space consultant Dr Stuart Eves.

"It's now in what we call a 'gravity well' at 105 degrees West longitude, wandering backwards and forwards like a marble at the bottom of a bowl. And unfortunately this brings it close to other satellite traffic on a regular basis.

"Because it's dead, the risk is it might bump into something, and because it's 'our' satellite we're still responsible for it," he explains.

If a satellite died at 40E it would drift to the nearest gravity well, which is 75E.

Dr Eves has looked through old satellite catalogues, the National Archives and spoken to satellite experts worldwide, but he can find no clues to the end-of-life behaviour of Britain's oldest spacecraft.

It might be tempting to reach for a conspiracy theory or two, not least because it's hard to hear the name "Skynet" without thinking of the malevolent, self-aware artificial intelligence (AI) system in The Terminator movie franchise.

But there's no connection other than the name and, in any case, real life is always more prosaic.

Quelle: BBC