The arrival of spring and early summer signifies the start of the noctilucent cloud season in the northern hemisphere.
These mesmerizing cloud formations, known for their radiant blue glow, can be observed during the summer months around 30 minutes after sunset against the darkening western sky.
Noctilucent clouds remain a fascinating enigma with an unclear origin. Positioned at an astounding altitude of approximately 80km (50 miles), they are the highest clouds in Earth’s atmosphere, nearly reaching the edge of space.
Despite their lofty position, they are deemed too distant and insubstantial to impact ground-level weather conditions.
What adds to the intrigue is the absence of recorded sightings of noctilucent clouds before 1885, which puzzles many, given their striking appearance. Several theories have emerged in an attempt to explain their sudden appearance.
One hypothesis suggests that these clouds may form when water freezes around industrial pollutants initially released into the atmosphere during the Industrial Revolution.
Another possibility is that the increased presence of the greenhouse gas methane in the atmosphere promotes water vapor production in the upper atmosphere, leading to the formation of these luminous clouds.
In the southern hemisphere, the noctilucent cloud season commences around October, offering a unique celestial spectacle for observers in that region.