Eerily perfect galaxy-shaped spiral appears over Hawaii. What is it?

A shot of the spiral-shaped light in the sky above Hawaii captured Jan. 18 by the Subaru-Asahi Star Camera on Mauna Kea.  (Image credit: National Astronomical Observatory of Japan) (opens in new tab)

An eerily-perfect "whirlpool" of light in the shape of a spiral galaxy briefly appeared in the night sky above Hawaii. 

But what was it?

It turns out the stunning spiral was comprised of frozen rocket fuel that was ejected during a SpaceX launch.

A video (opens in new tab) of the ethereal light show was captured Jan. 18 by the Subaru-Asahi Star Camera — co-owned by the National Astronomical Observatory of Japan (NAOJ) and Japanese news agency Asahi Shimbun — attached to the Subaru telescope on top of Mauna Kea, a dormant volcano on Hawaii's Big Island. In the sped-up footage, a small blob of light unfurls into a perfect glowing whirlpool that moves across the sky for several minutes before fading away into nothingness. 

"The spiral seems to be related to the SpaceX company's launch of a new satellite," NAOJ representatives wrote on Twitter (opens in new tab).

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A close-up of the illuminated spiral of frozen rocket fuel. (Image credit: National Astronomical Observatory of Japan) (opens in new tab)

The SpaceX launch in question was a Falcon 9 rocket that successfully lifted off from Cape Canaveral Space Force Station in Florida at 7:24 a.m. EST (1224 GMT) carrying a new GPS satellite for the U.S. Space Force, Live Science's sister site Space.com reported. 

The rocket's first stage, which provides the main propulsion for lift off, separated from the payload-carrying second stage around 3 minutes after launch and eventually returned to Earth. After separating from the first stage, the second stage used its small engine to propel itself into position to deploy the satellite. Once the satellite was deployed, any remaining fuel was then ejected before reentry, which caused the second stage to enter a spin before deorbiting and falling down to Earth in the Pacific ocean. The result was a cloud of frozen fuel crystals in the shape of a spiral, which were illuminated by sunlight, according to Spaceweather.com (opens in new tab). 

This is not the first time that SpaceX rockets have caused dazzling light shows. In April 2022, the Subaru-Asahi Star Camera captured a shimmering spiral of light after SpaceX launched a spy satellite into orbit on another Falcon 9 rocket.  

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The so-called "SpaceX spirals" are becoming "commonplace over the Pacific" because this is where most Falcon 9 rocket stages fall back to Earth, Spaceweather.com representatives wrote. 

Frozen rocket fuel has also created several other stunning visual anomalies in other parts of the globe. In March 2022, frozen fuel from a Chinese rocket created a large spinning orb of light that photobombed an aurora borealis in Alaska. In October 2017, an even larger blue orb was seen in the sky above Siberia, according to ScienceAlert (opens in new tab). On that occasion, Russian military rocket tests left the frozen fuel in the area.