If you looked up at the night sky on Monday and saw what looked like a glowing galaxy spinning above your head, you weren't alone — and you definitely weren’t imagining things.
From England to Wales and even parts of Europe, stunned stargazers watched as a bright, swirling spiral hovered in the sky.
For many, it looked like something straight out of a sci-fi movie.
Social media lit up with questions, videos, photos, and theories — some half-jokingly wondering if aliens had finally arrived. But the real explanation is just as spectacular, and it’s 100% made by humans.
What Were The Glowing Spirals Seen In The Sky?
The bizarre sight led to many people taking to social media to ask what the swirls could be. In fact, Google Trends shows a huge spike in searches from UK users regarding "sky spirals":
Fortunately, the Met Office quickly stepped in to clear up the mystery. The spiral, they said, was caused by none other than Elon Musk’s SpaceX Falcon 9 rocket.
"This is likely to be caused by the SpaceX Falcon 9 rocket, launched earlier today," the Met Office posted on X. "The rocket's frozen exhaust plume appears to be spinning in the atmosphere and reflecting the sunlight, causing it to appear as a spiral in the sky."
The Falcon 9 had launched from Florida's Kennedy Space Center at around 1:50PM local time (5:50PM GMT) on March 24.
It was part of a classified US government mission for the National Reconnaissance Office.
A Stunning Side Effect of Rocket Science
So why did it look like a glowing whirlpool in the sky?
As the Falcon 9 returned to Earth after releasing its payload, it dumped leftover fuel — a standard safety move to avoid explosions on re-entry.
That excess fuel froze instantly due to the altitude. Because the rocket is spinning as it comes back down, the frozen exhaust formed a spiral pattern that reflected sunlight, lighting up the night sky below, BBC News reports.
Professor Brian Cox confirmed it was a frozen plume from the Falcon 9, and the Met Office wasn't the only one to back it up.
Astronomer Allan Trow, who saw the spiral above Wales’s Bannau Brycheiniog National Park around 8:00PM GMT, said: “These are pretty rare,” but agreed it was most likely the rocket.
“It Looked Like a Swirling Galaxy”
Across the UK, people caught the rare display — and they had a lot to say.
In one tweet, Trow described the sight as a "portal to another world".
Steven Hall was taking the bins out at his home in rural Suffolk when he saw what looked like "a huge Catherine wheel which appeared to have its own atmosphere around it."
"It did pass my mind, is this an unexplained, unidentified flying object?" he admitted to the BBC.
Meanwhile, a sky-watcher in Lytham St Annes, Lancashire, said the swirl "started off as a bright light, then [had] a blurry ring around it and then a spiral." They added: "[It] hovered over this church for about five minutes then started moving and disappeared."
Sonia, an amateur astronomer in Stockport, was already out with her telescope when she spotted "a swirling galaxy that was moving across the sky."
Keeley Williams, who watched from Ivinghoe Beacon in Buckinghamshire, said it “started off hazy, then became really bright before looking like it was spinning.”
The spiral wasn’t limited to one part of the country either.
Photos of the phenomenon came in from Bulwick in Northamptonshire, Clee Hill in Shropshire, Gwynedd in Wales, Castleford in West Yorkshire, and even as far away as Denmark and Milan, Italy.
Whether you were taking the trash out or scanning the stars, it’s fair to say this was one night sky show no one expected — or will forget any time soon.