The Glowing Jellyfish over California
Just after sunset one December evening, a glowing shape like a giant jellyfish spread across the sky over California. Many people thought it was a UFO or a missile.
What was reported
On the evening of 22 December 2017, people across southern California, and as far away as Arizona and Nevada, saw a strange, glowing cloud cross the sky. It had a bright point at its head and a huge, luminous plume spreading behind it like a jellyfish or a comet.
Social media filled with videos and guesses: aliens, a missile attack, a meteor. Some drivers pulled over on the freeways to watch.
Explanations offered
It was a SpaceX Falcon 9 rocket launching satellites from Vandenberg Air Force Base. The launch happened just after sunset, so people on the ground were in darkness while the rocket's exhaust, high above, was still lit by the Sun. The thin air at that height let the plume spread out into a glowing cloud. Launches at twilight have caused similar scares elsewhere.
- When
- 22 December 2017
- Where
- Vandenberg Air Force Base, California, USA
- Witnesses
- Thousands of people across California, Nevada and Arizona
- Status
- Explained
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.
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