World Mystery: Black Knight Satellite mystery and Possible Explanation.

Story:

Legend has it that in orbit around the Earth is a mysterious, dark object which dates back perhaps 13 000 years. Its origin and purpose are inscrutable, dubbed the “Black Knight” this elusive satellite has allegedly been beaming signals towards the Earth and inspected by NASA astronauts yet only a few on Earth officially know of its existence.

The origin of the ominous name is part of the enigma; it is impossible to discover who first called it this or indeed why. Humans have only in the last 60 years had the technology to launch a man-made object into space so what is the logical explanation of tales of an alien intruder on our doorstep?

Explanation:

Some people think it’s a thermal blanket that had been lost during an Extravehicular activity
  or just some space debris.