Mystery Flying Whirlpool Filmed Over Hawaii Was Dead SpaceX Rocket

A mysterious swirling whirlpool spotted in the sky over Hawaii on Sunday has been revealed to have been the death spiral of the upper stage of a SpaceX Falcon 9 rocket.

The phenomenon was dubbed a "flying whirlpool" by operators of the Subaru-Asahi Star Camera, part of the Subaru Telescope located on the dormant volcano Mauna Kea, which filmed its passage through the sky.

While the spinning object may resemble a shockingly close spiral galaxy whipping through space past the Earth, its origins actually lie closer to home.

Rocket Spiral
A screenshot taken from a video shot by the Subaru Telescope showing the upper stage of a Falcon 9 rocket in a death spiral forming a whirlpool like image over Hawaii. Subaru Telescope

The whirlpool was spotted just hours after a National Reconnaissance Office (NRO) classified satellite payload was launched atop one of Elon Musk's SpaceX Falcon 9 rockets as part of the NRO Launch 85 (NROL-85) mission. This means the spiral is actually the aftermath of that launch.

The SpaceX Falcon 9 launched from Space Launch Complex 4 East (SLC-4E) at Vandenberg Space Force Base in California at 6:13 a.m. PT on April 17. The booster had previously launched NROL-87 mission, making this the first time an NRO satellite had launched on a used rocket.

The SpaceX rocket's two stages separated about 2.5 minutes after launch with the first stage heading back to Earth and touching down at Vandenberg Air Force Base's Landing Zone 4 complex five and half minutes after separation in what seemed to be a flawless launch, Space.com reported.

The death spiral is the upper stage of the Falcon 9, which unlike the lower stage which successfully executed a vertical touch down at Vandenberg is not designed to be reused. this means the upper stage is allowed to fall back into the atmosphere and burn up.

A researcher at the Astronomy Department of Leiden University, Marco Langbroek, told Newsweek: "The video shows the upper stage of a SpaceX Falcon 9 rocket venting left-over rocket fuel just before reentering into the atmosphere over a safe area in the
Pacific.

"The vented rocket fuel droplets form a cloud in space that is illuminated by
sunlight and hence becomes visible as a glowing cloud."

Langbroek added that this venting of fuel remnants from the tanks is a standard procedure performed after the rocket engine does its final 'deorbit burn.' The purpose is to avoid fuel vapors from remnants of fuel in the tank exploding.

He continued: "You don't want that to happen, certainly not while the rocket stage is still in space, as it can create space debris.

"Also, such an explosion could mean that fragments of the rocket stage could come down too early, not over the safe area you designated for that. That is obviously something you want to avoid."

In the video, uploaded to the Subaru Telescope Youtube channel, the rocket can be seen spinning as it passes from the left-hand side of the screen to the right. As it moves, it fades and falls closer and closer to the surface of Earth.

This isn't the first time that a rocket has created a mysterious spiral in the night sky over Earth.

In January this year, another SpaceX rocket, this time launching from Cape Canaveral Space Force Station, created a fiery spiral over the skies of Oklahoma, CBS News reported.

The phenomenon was captured by meteorologist Lacey Swope who uploaded stunning images to her Facebook page on February 1.

GALAXY SPIRAL OVER OKLAHOMA: Did you see this tonight?? Brent Carter near Agra, Casey Evans from Kiefer, Jason Harp from Ponca City, and Ryan Joplin from Deer Creek sent these pics. From what I can...

Langbroek added: "A very similar spiral cloud was photographed by a Dutch commercial pilot over East Africa following the (ill-fated) Zuma spy satellite launch, also by SpaceX,
on January 8, 2018. It was photographed from several other locations in East Africa too at that time.

"The 'spiral' probably results from rotation of the rocket stage—we
have seen this more often with Falcon 9 fuel vents. This spinning is probably intentional—spinning the rocket stage over its long axis is a way to stabilize the attitude of the rocket stage and in that way control drag from the upper atmosphere on the stage.

"That is important to have the stage enter the atmosphere in the designated area."

Langbroek concluded by saying that other rockets can create differently shaped phenomena: "I personally observed a fuel vent connected to the launch of the Landsat 9
satellite last year, on 27 Sept 2021, from Leiden, the Netherlands, which was
spectacular to watch.

"This was not a spiral-shaped one—due to another rocket
type used for that launch—but V-shaped, another frequent shape for these events."

Newsweek has asked SpaceX for comment.