Bill Cooke of NASA's Meteoroid Environmental Office said the widely-reported flash in the sky was probably "a single meteor event." He told the Associated Press:
[It] looks to be a fireball that moved roughly toward the South East, going on visual reports.
Judging from the brightness, we're dealing with something as bright as the full moon.
The thing is probably a yard across. We basically have [had] a boulder enter the atmosphere over the North East.
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Mayor of London Sadiq Khan is backing the scheme.
Sunday will be a fine day across much of Scotland and northern England, with much less coastal mist and low cloud than yesterday.
A spokesperson said the lightning strikes had left the "aircraft fuelling system unavailable."