Meteorologist explains bright lights seen over Crete and Athens

Meteorologist Thodoris Kolydas has provided an explanation for the bright lights observed in the night skies over Crete and Athens on Tuesday night. While the sightings led to widespread speculation on social media regarding UFOs, experts clarify that the event was a known optical phenomenon.

The phenomenon is caused by gases and propellant residues released from the upper stage of a rocket at extremely high altitudes. In the thin atmosphere of the upper layers, these materials expand rapidly, creating large formations. These can appear as spiral or circular shapes depending on the rotation and orientation of the rocket stage.

The visibility of the lights is attributed to the ‘twilight effect’. Although it is dark for observers on the ground, the cloud of particles at hundreds of kilometers in altitude remains illuminated by sunlight because it sits above the Earth's shadow. This sunlight reflects off the particles, making the formations appear white, blue, or slightly colored against the dark sky.