The eyes and interest of bathers in southeastern Attica were drawn to a “solitary” cloud that appeared to be crossing the sky on Tuesday evening, shortly before sunset.

As can be seen in images from Saronida beach, there were no other clouds in the sky at the time, prompting a variety of comments, including speculation that it might have been an unidentified flying object.

According to reports, residents of several other areas also saw the same unusual cloud. In fact, many reports came from Crete.

Kolydas’s Explanation

Former director of the National Meteorological Service Theodoros Kolydas provided a possible scientific answer to the mystery that sparked so much discussion.

As he claimed in a post on X, “this is a well-known optical phenomenon that can be created by gases and remnants of rocket propellants at very high altitudes, as has been repeatedly observed during SpaceX Falcon 9 rocket launches.”

As for the question of why the particular cloud was glowing, he noted: “This is perhaps the most beautiful part of the phenomenon. While it is already night for an observer on the ground, at an altitude of hundreds of kilometers the cloud may still be illuminated by the Sun, because it is above the Earth’s shadow.”