On the evening of March 24, residents of many European countries witnessed the appearance of an unidentified flying object. They saw a strange ghostly spiral that moved across the sky from west to east. But while the phenomenon was indeed space-related, it had nothing to do with aliens or military testing.
The celestial spectacle, witnessed by Europeans, and images of which flooded social networks, is called a space jellyfish. It results from the reflection of light from the cloud of gases surrounding the rocket, which have been produced by the operation of its engines and/or the venting of residual propellant. The jellyfish can usually be seen in the sky either before dawn or shortly after sunset. Due to their unusual appearance, they are often mistaken for UFOs or even nuclear tests.
The source of the space jellyfish was a Falcon 9 rocket launched on March 24 from Cape Canaveral. The purpose of the mission was to place the military satellite NROL-69 into orbit. After separation, the rocket’s first stage returned to the spaceport and landed on the ground. The second stage continued the flight and put the satellite into a western orbit.
After separating the satellite, SpaceX specialists proceeded to perform a standard maneuver to bring the Falcon 9 second stage down from orbit. At 21:00 UTC, when the rocket was over Europe, they restarted its engines. This is what led to the formation of the highly visible jellyfish observed in countries such as the UK, France, Italy, Poland and Germany.
As for the maneuver itself, it resulted in success. The Falcon 9 second stage burned up in the atmosphere above the Indian Ocean.
