Sightings have been reported of a green 'fireball' flashing across the sky over Lincolnshire.
Lincoln City goalkeeper Paul Farman was among those who saw the phenomenon and wrote on Twitter at about 9pm that he'd seen a meteoroid or a shooting star.
RAF Waddington spokesman Lindsey Askin said no flights from the base were in the air over Lincoln.
Astronomer Paul Money, who lives in Horncastle, caught a glimpse of the spectacle out the corner of his eye as it disappeared to the north.
"It is difficult to say whether this was a chunk of man-made space debris or a piece of asteroid," he said.
"Images and eyewitness reports will be collated by the British Astronomical Association and some months down the line they may get an idea of what it actually was."
Astronomer Philip Norton, of Thirsk Drive, North Hykeham, said: "From the description on the web it sounds like a lump of rock about the size of a football hit the atmosphere. This is not uncommon. It just never seems to happen over the UK when the sky is clear.
"What is more interesting is asteroid 2012 DA14. At teatime on February 15 it will pass by only 17,000 miles above the surface.
"This is below the orbits of the TV satellites. Asteroid 2012 DA14 is a little guy, compared to some asteroids, although its size has not been pinned down precisely.
"It is thought to be about 150 feet across, with an estimated mass of about 130,000 metric tonnes. If it hit the Earth it would form a crater several miles across. It will only be visble in binoculars."