Post SpaceX's Falcon 9 launch, a glowing spiral stunned skywatchers — here's what caused it

Stargazers in Europe photographed the unexpected celestial display on the night of June 23.
PUBLISHED JUN 26, 2025
Falcon 9 launching payloads on the Transporter-14 rideshare mission. (Representative Cover Image Source: X | SpaceX)
Falcon 9 launching payloads on the Transporter-14 rideshare mission. (Representative Cover Image Source: X | SpaceX)

Europe was treated to an unexpected celestial display on the night of June 23, as the upper stage of a SpaceX Falcon 9 rocket created a strange, visible plume of expelled propellant, captivating stargazers across the continent, as per Space.com



 

The dazzling spectacle originated from SpaceX's Transporter-14 mission, which had launched earlier that day at 2:25 p.m. PT from Space Launch Complex 4E (SLC-4E) at Vandenberg Space Force Base in California. This dedicated Smallsat Rideshare Mission successfully deployed 70 commercial payloads into low-Earth orbit, ranging from cubesats and microsats to re-entry capsules. A notable detail of the launch was the first stage booster, which completed its impressive 26th flight, underscoring SpaceX's advancements in rocket reusability, as mentioned on SpaceX.  



 

After its primary task of deploying satellites, the Falcon 9's upper stage performed a routine fuel purge, releasing its remaining rocket propellant before beginning its re-entry into Earth's atmosphere. This expelled fuel rapidly froze in the cold upper atmosphere, and, reflecting the Sun's light, became a diffuse, glowing cloud visible to the naked eye.

Night-shining, or noctilucent clouds on July 3, 2011, in Lock Leven, Fife, Scotland (Image Source: NASA |  )
Night-shining, or noctilucent clouds, on July 3, 2011, in Lock Leven, Fife, Scotland (Image Source: NASA | Photo by Adrian Maricic)

The ethereal phenomenon did not go unnoticed. The Virtual Telescope Project's all-sky camera in Manciano, Italy, successfully captured the diffuse cloud of particles at 8:13 p.m. EDT on June 23 (0013 GMT June 24), with the soft glow of the Milky Way serving as a cosmic backdrop. Similarly, Oxfordshire-based astrophotographer and science communicator Mary McIntyre documented the plume's rapid transit over the United Kingdom, utilizing specialized meteor and aurora-hunting cameras for time-lapse videos, as reported on Space.com. 



 

Stargazing enthusiast, Jure Atanackov, also reported on X an "unusual sight in the skies over Europe this morning," describing a "brief (<10 min) bright elongated luminous cloud" that appeared between 00:10 and 00:20 UTC. He noted its likely origin as a "rocket plume (propellant dump?)" and that it was spotted by webcams over the Alps, disappearing by 00:30 UTC. 



 

While the appearance of such plumes is not entirely unprecedented, having been observed after previous Falcon 9 rideshare missions where fuel purges are commanded, this particular event lacked the defined swirling structures sometimes seen in rocket exhaust. The sighting also brings renewed attention to the potential connection between rocket propellant and the formation of high-altitude noctilucent clouds. These "night shining" clouds are more commonly at higher latitudes, but in recent decades, their appearance closer to the equator has prompted scientists to consider whether rocket exhaust plays a role in their formation. 

Noctilucent Clouds taken from 36,000 feet above the South of Nunivak Island, Alaska on June 20, 2006 (Image Source: NASA)
Noctilucent Clouds taken from 36,000 feet above the South of Nunivak Island, Alaska on June 20, 2006 (Image Source: NASA)

These rare atmospheric phenomena, noctilucant clouds, are collections of ice crystals that become visible in the twilight hours of late summer evenings, just as the brightest stars appear or even after dark, because they are still high enough in altitude to reflect sunlight. Noctilucent clouds occupy the Mesosphere — the highest layer of Earth's atmosphere where clouds can form. They are typically observed at latitudes between 45°N and 80°N in the Northern Hemisphere, with fewer sightings in the Southern Hemisphere due to limited landmass at equivalent latitudes. The formation of noctilucent clouds requires water vapor, dust, and extremely low temperatures. Scientists believe dust may come from tiny meteors, while moisture might originate from the tropopause or chemical reactions like those involving methane, according to the MET Office

MORE STORIES

Despite its frigid, ice-covered exterior, Saturn's moon 'Enceladus' has become a primary target in the search for extraterrestrial life.
16 hours ago
Astronomers, led by Dr. Phil Massey of Lowell Observatory, have identified a colossal pair of stars in one of the Milky Way’s most vibrant star-forming regions.
1 day ago
Whether the planet GJ 1132 b had an atmosphere was long debated due to conflicting old data.
3 days ago
The space agency found the aftermath of massive impacts beneath the planet’s surface using the recordings of the InSight lander.
4 days ago
The knowledge of how planets formed might now be getting a massive twist due to ALMA's new findings.
4 days ago
The data could provide new insights into the comet’s chemical makeup and physical features as it zooms through our system.
5 days ago
Since it was discovered in 1977, the 'Wow!' signal has been one of the most mysterious radio signals in SETI history.
5 days ago
Astronomers estimate that the planet is about 5 million years old and is similar in size to Jupiter.
6 days ago
New studies suggest that collapsing gas clouds in the early universe may have also formed lower-mass stars.
6 days ago
A recent study proposes that a computational technique known as numerical relativity could be the key to unraveling some of the universe's most profound mysteries.
7 days ago