Details and predictions about possible future observations of spirals
A large swirl of bright light appeared in the night sky over the Arctic last week. Astronomers call this phenomenon the «SpaceX spiral» and expect it to become much more common in the future.
The phenomenon occurred on March 4 during the launch of SpaceX's Falcon 9 rocket from Vandenberg Space Center in California. The Transport-10 mission included 53 satellites belonging to various commercial space companies, which were successfully launched into orbit approximately two hours after launch. Shortly after the payload was deployed, the second stage of the rocket, separated from the first, began deorbiting and burned up in the atmosphere over the Barents Sea. In the process, the rocket ejected the remaining fuel, which froze into tiny crystals and reflected the light of the sun.
Photographer Shan Yang captured this moment near the city of Akureyri in Iceland: «It's a stunning sight, especially against the backdrop of the northern lights»,— Shan said. The spiral of light lasted about 10 minutes before dissipating.
The light show was also observed during the live broadcast of the northern lights in Iceland, and was also seen in Finland and Norway, where it had a bright blue hue.
Although such phenomena are rare, they are becoming more common as the number of SpaceX launches increases. Earlier, in April 2023, the «SpaceX spiral» complemented the aurora over Alaska. The phenomenon was also spotted twice by the Subaru Telescope camera on the Hawaiian island of Mauna Kea: once in April 2022 and again in January last year.
The appearance of spirals depends on various factors, such as the speed of rotation of the launch vehicle, the time of day and the orientation of the rocket in relation to the Earth and the Sun. Therefore, it is difficult to predict the exact date of the next observation.
However, astrophotographer Olivier Steiger was able to foresee the phenomenon of the «SpaceX spiral» in this case. He noted that the specific nature of the Transporter 10 mission required the rocket to spin more, which meant it continued to spin while jettisoning fuel. He also predicted that SpaceX could expect another spiral of light from SpaceX when the Transporter 12 mission launches over Iceland and other parts of the Arctic this October.