Shapes in the sky seem to appear out of nowhere: an S-shaped spiral has been spotted in the sky of Europe.
These strange light displays have been known to be the result of rocket launches for years. But as humanity rapidly increases the number of objects launched into space, more people are now witnessing the phenomenon, CNN wrote.
"We're not used to seeing things happening in space at such a low atmospheric density," said Jonathan McDowell, an astronomer.
When SpaceX's Falcon 9 rocket launched from Florida last week, it caused a celestial spectacle for millions of people in the UK and the European continent.
Shortly after the rocket's launch, people started writing on social media about "strange shapes" in the sky.
The display was likely caused by a missile, a post from Britain's meteorological service said.
However, seeing such a display associated with a rocket launch can be difficult and requires precise timing and darkness.
But the number of rockets launched from the ground has increased, going from fewer than 150 per year in the 20th century to over 250 last year, according to McDowell.