In 1899, he reportedly intercepted a signal unlike any of the natural sources from Earth such as electrical storms that he had already investigated in his experiments. Tesla never claimed to have heard signals from a satellite orbiting Earth.

Today there are those who say he was listening to a transmission from an orbiting satellite of unknown origin later called by some the Black Knight.

It is slightly more likely, though still very far from probable, that what was Tesla detected was not an orbiting satellite but instead signals emitted from natural objects.

Today we know of some natural extraterrestrial repeating sources such as pulsars.

Yet the discovery of an Earth-orbiting satellite was reported in a couple of newspapers from the time, and the respected Alias Corona A few years later, the Black Knight seemed have made another appearance when American newspapers reported in 1960 that there was an unusual object in polar orbit, by then both superpowers had satellites in equatorial orbit but polar orbit meant that the satellite could see every part of the Earth, yet neither country admitted owning it.

This may seem strange but remember that this was a time of deep-rooted suspicion and espionage not just with each other but now seemingly with extra-terrestrials too.

So although claims of an ancient 13 000 year old satellite originally from a star in the constellation of Böotes, has reportedly been spotted and photographed by NASA astronauts as it travels in polar orbit; in reality this is not the case.

Black Knight is a jumble of completely unrelated stories; reports of unusual science observations, authors promoting fringe ideas, classified spy satellites and people over-interpreting photos.

The Tesla Transmissions The first apparent part of this story begins with signals heard by Nikola Tesla (1856-1943) a brilliant Serbian inventor (and described by many thanks to his often eccentric behaviour and opinions as a genuine who spent most of his career in the USA.

He was an electrical engineer and produced works which explored the idea of radio and wireless transmissions.

The crew of Space Shuttle Orbiter Endeavour photographed an unusual object in low Earth orbit (but not a polar orbit).

These images are often labelled as the most definite proof of this satellite.

When you have admitted seeing UFOs once perhaps other details of when and where often become less significant.