If you happened to be in Europe on March 24th, 2025 and you looked up into the night sky, you may have seen something quite surprising.

A giant swirl of blue light appeared, leaving many people mystified.

Was it aliens?

No. Instead it is said to be from the launch of SpaceX’s NROL-69 Mission, which is classified.

SpaceX did confirm that this launch took place on their website, saying:

“On Monday, March 24 at 1:48 p.m. ET, Falcon 9 launched the NROL-69 mission from Space Launch Complex 40 (SLC-40) at Cape Canaveral Space Force Station in Florida. This was the second flight for the first stage booster supporting this mission, which previously launched a Starlink mission.”

According to a 2024 Reuters interview, SpaceX is working with the National Reconnaissance Office (NRO) on technology that could be used to help with spy satellites. SpaceX may be sending up large numbers of smaller satellites that are able to coordinate together in a swarm in low-Earth orbit. They can then be used to image the Earth.

The launch was successful, but the fuel from it spread across the skies in this blue spiral, making it quite a spectacle to see. The spiral pattern is caused by the Falcon 9 rocket’s exhaust system. This was explained on a post on X:

“We’ve received many reports of an illuminated swirl in the sky this evening. This is likely to be caused by the SpaceX Falcon 9 rocket, launched earlier today. 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.”

Similar patterns have been seen during previous launches, though typically not as bright due to differences in the time and location of the launch. In a statement after a previous launch, geophysicist Don Hampton (Poker Flat Rocket Range chief scientist) explained:

“It is likely either exhaust from a rocket burn to bring the second stage down over the Pacific, or perhaps dumping extra rocket fuel after that burn. The spiral pattern indicates that the second stage was spinning when it exhausted the gasses. Any water vapor would turn into ice at these altitudes, and the ice would reflect sunlight where the rocket was, and make a bright cloud visible on the ground in Alaska where the sun was well below the horizon. It looks really bright in those pictures, but it is likely just a few pounds of water.”

So, while not as exciting as aliens, the bright light certainly was beautiful and will likely be something that is seen more in the future.

If you weren’t lucky enough to catch it in person, you can see it in this brief YouTube video:

I wish I had seen it.

Then I could decide for myself.

If you thought that was interesting, you might like to read about the mysterious “pyramids” discovered in Antarctica. What are they?