11 hours ago
Mysterious 'Jellyfish UFO' spotted over US desert as scientists reveal its origin
A strange jellyfish-like phenomenon was spotted streaking across the California sky Monday night.
While the unusual ' UFO ' sighting baffled many locals from the Mojave desert to Los Angeles 's South Bay, scientists say there were no extraterrestrials involved in creating the jellyfish - it was an Elon Musk rocket.
SpaceX 's latest Falcon 9 rocket mission lifted off at 11:36pm ET Monday night from Vandenberg Space Force Station in California.
A few minutes into the flight, the rocket's exhaust interacted with the atmosphere, creating a visible cloud of condensed water vapor.
Since the launch took place right after sunset, around 8:36pm PT, the sun illuminated the crystalized exhaust plume, resulting in a spectacular sight for millions on the ground.
Californians posted images of the rocket soaring over the state on X, even as far south as Riverside, over 200 miles southeast of the Vandenberg launch site.
SpaceX's lead avionics systems engineer, Cameron Gable, captured the jellyfish phenomenon as the rocket traveled past Los Angeles County's South Bay.
The mission, dubbed Starlink 15-9, saw SpaceX launch its latest batch of Starlink satellites into low Earth orbit.
The jellyfish phenomenon, also known as a 'vapor cone' or 'shock collar,' occurs when the localized air pressure around the rocket drops, causing the air temperature to decrease and water vapor to condense into visible clouds.
Monday's giant jellyfish display started just a few minutes into the flight and was visible to anyone in the Southern California area.
It's not the first time a SpaceX rocket has produced the jellyfish effect. In October 2022, sky watchers caught another Falcon 9 rocket creating the same vapor trail during a similar mission to deploy new satellites.
Monday's Falcon 9 launch was the latest mission in SpaceX's ongoing efforts to expand its Starlink 'constellation,' aiming to enhance global internet coverage.
SpaceX has already conducted 75 launches in 2025, mainly for Starlink missions.
The mission also used a reusable first-stage engine, a hallmark of SpaceX's design philosophy aimed at reducing the cost of spaceflights.
SpaceX captured the moment on their live broadcast when the reusable engine safely landed back on Earth to be used again in future missions.
Monday's mission was the 200th from the company's Space Launch Complex 4 East at Vandenberg.
The jellyfish effect is a common occurrence during space rocket launches and can normally be seen from states hundreds of miles from the actual launch site
The remote-controlled reusable rocket engine made a perfect touchdown on SpaceX's droneship in the Pacific Ocean about eight minutes after launch, making it the 463rd engine returned to Earth.
While the jellyfish effect may seem like a bizarre UFO to the untrained eye, it's common among spaceflights.
Social media users regularly capture rockets giving off the jellyfish trail from hundreds of miles away.
One X user in Phoenix, Arizona, was able to spot a similar jellyfish during a June 2024 launch. That mission also involved a Falcon 9 launching from Vandenberg, which was over 500 miles away.
When a rocket launches, it expels a large amount of exhaust gases at high speeds. These gases, primarily composed of water vapor, carbon dioxide, and other rocket launch byproducts, expand rapidly as they exit the rocket's nozzle.
As the exhaust plume expands, it encounters cooler, denser air in Earth's upper atmosphere. This can cause the water vapor in the exhaust to condense into visible clouds, forming a balloon-like shape around the rocket.
The high speed of the rocket can also create shock waves, further shaping the exhaust into distinctive patterns, creating the jellyfish effect.
SpaceX's Falcon 9 rockets, with their frequent launch schedule and reusable first stages, often trigger this effect due to their design and the typical launch times chosen for optimal visibility.
However, any rocket launch around the world can potentially give off a jellyfish trail, especially when the conditions are right for the exhaust to give off a dramatic display in the atmosphere.
