A mysterious 'asteroid' discovered in orbit around Earth that baffled astronomers turns out to be man-made.
The strange object identified as '2013 QW1' was discovered in August from data taken by the PanSTARRS sky survey in Hawaii.
Though it appeared as little more than a blip on a screen, the object immediately intrigued researchers. It was caught in a wide orbit around Earth, and it was difficult to tell if it really was an asteroid which had been captured by the Earth's gravity, a piece of debris from a space mission, or something even more strange.
It was even proposed that the object (above) might be a tiny 'second moon' - which would be interesting - as Universe Today notes, because the actual Moon usually keeps our skies clear of these types of objects.
The identity of the object remained a mystery until taken up by the European Space Agency's NEO Coordination Centre, who with the help of researchers at the Observatoire de Paris managed to track it with an Italian telescope.
In a press release one of the team, Davide Perna, said that finding the asteroid "was a bit of a challenge, because the object was moving fast".
But despite the challenge the object was identified as artificial. ESA says it's probably a booster stage rocket.
"The observations by European astronomers coordinated by ESA demonstrated a very quick reaction in getting high-quality data that conclusively identified the object as artificial, and hence no threat," said Detlef Koschny, responsible for NEO activities at ESA's Space Situational Awareness programme office.