A colourful big halo around the sun on Wednesday afternoon mesmerised many in Hyderabad. Photos and videos of the halo soon flooded social media platforms, with many sharing their opinions and some drawing comparisons to a similar sight from Bengaluru recently.
As the unique spectacle coincided with Telangana’s eighth state formation day celebration on June 2, many considered it a ‘blessing’. At the same time, much misinformation and misconceptions were also shared. Some called it a bad omen ahead of a catastrophe, while some linked it to the upcoming solar eclipse.
Raghunandan Kumar, the founder secretary and director at Planetary Society of India, clarified that the halo was a local weather event. He said a similar weather phenomenon had been observed in the Yadadri district a few days ago. On Wednesday, he said the ’22-degree halo’ lasted for an hour-and-a-half and was observed from Hyderabad and surrounding districts.
They are called ’22-degree halos’ because for an observer, the ring has a radius of approximately 22 degree around the sun or moon. The halos are caused by refraction, or splitting of light, and also by reflection, or glints of light from hexagonal ice crystals, he said, adding that the phenomenon works on the principle of a kaleidoscope and has evoked much scientific interest in the minds of youngsters.
Such a halo is a common occurrence with the moon during winters. “It is not something rare. It is caused because of thin cirrus clouds drifting at 20,000 feet or above. These clouds contain millions of tiny ice crystals. The sunlight or moonlight passing through these gets refracted and reflected. It is so common you can see such halos around street lights during winters,” Raghunandan Kumar explained.
Just like a rainbow, a 22-degree halo is an extremely local weather event. “But surprisingly, today’s halo was observed from Sangareddy, Nalgonda, Siddipet and Rangareddy districts other than Hyderabad. Contrary to what some people claim, this event has nothing to do with the recent lunar eclipse, blood moon, or upcoming solar eclipse,” he said.