The UK’s oldest satellite has moved and no one appears to know exactly who did it, when or why.
Skynet-1A, which was launched in 1969, is now around half a planet away from where it was launched, floating 22,369 miles above the Americas.
The half-tonne military spacecraft was initially put above Africa’s east coast to relay communications for British forces as far away as Singapore.
Experts have said it is unlikely that Skynet-1A simply drifted to its new position due to orbital mechanics.
Instead when the satellite stopped working a few years after its launch, gravity should have pulled it east, out over the Indian Ocean.
Now it seems certain it was commanded to take itself westwards in the 1970s but it is unclear who gave that order.
Space consultant Dr Stuart Eves told BBC News: ‘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.’
It currently runs the risk of a piece of junk coming within 50km or its position up to four times a day – a distance which is a little too close for comfort.
Dr Eves explained he hasn’t been able to find any clues about the end-of-life behaviour of Skynet-1A in old satellite catalogues or the National Archives.
Skynet-1A was manufactured in the US by aerospace company Philco Ford just a few months after humans first set foot on the moon.
It was then launched into orbit in 1969 from Florida by a US Air Force Delta rocket before control was handed over to the RAF.
Experts have said it is unlikely that Skynet-1A (pictured) simply drifted to its new position due to orbital mechanics
Graham Davies, who flew Skynet-1A in the early 70s from the RAF Oakhanger base in Hampshire, said while it its possible control was given back to the Americans, it is ‘unlikely’.
Whereas, Rachel Hill, a PhD student from University College London, explained that control of the satellite was briefly transferred to the US when Oakhanger was shut for maintenance.
She said it was possible that the location shift occurred then.
Skynet-1A official albeit incomplete logs suggest it was left in control of the Americans when the RAF lost sight of it in June 1977.
However, this would mean that the satellite was left to die in an ‘awkward place’ when normally space junk is placed in a designated ‘orbital graveyard’.
Orbital graveyards are areas where disused spacecraft is unlikely to run into active telecommunications satellites.
While this is now a practice used regularly in the space industry, it was not commonplace in the 1970s.