Major fireball seen over UK was probably space junk returning to Earth

Planetary scientists are racing to establish the origin of a bright fireball seen over parts of the UK on 14 September – the evidence so far points to it being space junk rather than a meteor

By Will Gater

Planetary scientists are working to establish the origin of a bright fireball seen over Scotland, Northern Ireland and northern England on the evening of 14 September.

The spectacular event, spotted at about 10pm local time, was caught in numerous videos on social media, which showed a dazzling whitish-green light moving at speed across the sky, in some cases with a trail of glowing material behind it.

At the time of writing, around 900 eyewitness accounts had been submitted to an international catalogue of fireball events maintained by the American Meteor Society and the International Meteor Organization. Some observers even reported hearing a rumble following the event, which initial analysis suggests occurred over a region near the islands of Islay and Arran in Scotland.

It isn’t yet clear if the fireball was the result of a meteoroid – a natural space rock – entering Earth’s atmosphere and becoming a meteor, or the re-entry of a piece of debris from human space activity, although early evidence does point to the latter.

“There is a reasonably high chance that this is space junk, unfortunately. [The fireball] had a very shallow entry angle, a substantial amount of fragmentation, which is typical of space junk, and it looks slowish. Space rocks tend to be a bit faster. However, we’re still crunching the numbers to get a good estimate on the velocity which will tell us for sure whether this is space rock or space not,” says Luke Daly, a planetary scientist at the University of Glasgow, UK, and member of the UK Fireball Alliance.

“Meteors typically enter the atmosphere at very high speeds, 75 to 80 thousand miles per hour,” says John Maclean at the UK Meteor Network, whose cameras captured the phenomenon. This would equate to between about 121 and 129 thousand kilometres per hour. “Space junk would be much slower, at maybe 25 to 30 thousand miles per hour depending on the original orbit velocity.”

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