Multiple people have taken to social media to share videos and pictures of what seems to be an unidentified aerial phenomenon (UAP), which saw clouds from Ealing to Walthamstow changing colours.
Social media has been quick to speculate about the reasons – with some people blaming aliens.
One Twitter user said: “Saw some UAP earlier in West Ealing. Any idea what this could be? No sound i.e.. like a helicopter etc. but the lights were slowly moving.”
For the moving blue lights seen in Ealing one Reddit user suggested it might be a special train used to inspect overhead power lines.
The new Network Rail measurement trains record the tracks and the structures around them to make sure they’re in full working order and have been spotted in Teeside and Bristol before.
This does not explain the lights seen more than 15 miles away in Walthamstow though, with one user suggesting the lights came from a fountain in Fellowship Square, Waltham Forest.
But, given the weak strength of those lights there is a more likely explanation in the form of a new City of London light show planned for the winter.
The Northern Lights display will bring the world famous natural wonder of the Aurora Borealis to Guildhall Yard in December.
After seeing the strange lights in the sky last night, some Londoners think planners might have been testing their equipment.
Reports of the lights have also come from Peckham and Sydenham, suggesting whatever caused the display is very powerful.
Aside from aliens, light shows, and trains, social media users have also offered a few more alternative theories.
For example: “God is having a rave”, “It’s the bat signal”, and “The rapture”.
The most likely explanation though might simply be extra terrestrials, intent on invading the earth and destroying humanity.
Luckily for humans, one user joked: “Aliens were going to land and make contact, but then they saw it was Walthamstow!”
MyLondon has asked the City of London to confirm if the lights were part of the new display.