From AMK to Pasir Ris, Stompers share photos of 'full circle rainbow' -- but it's actually a sun halo
It was so rare and spectacular that even former Prime Minister Lee Hsien Loong shared photo of it.
So did a number of Stompers.
Stomper Cai said he spotted the rare "full circle rainbow" on March 15 at 12.20pm at Mayflower Avenue in Ang Mo Kio.
Another Stomper said: "A circular rainbow appeared in the sky in Hougang at about 2pm."
A Stomper in Pasir Ris shared a photo of a "round rainbow" above their block in the morning.
Another Stomper said he saw the "natural phenomenon" at about noon
Calling it a "full rainbow", Stomper Wu declared: "What a beautiful, beautiful scene."
Sharing a photo taken at Shenton Way, Stomper Ashish described it as a "rainbow wrapping the sun, magic in the sky" and referred to it as a "rare sight".
One Stomper simply said: "Look up, please!"
Stomper Terry described it as a "rainbow around the sun".
Sharing a video, another Stomper initially called it a "full rainbow" before asking: "Or is it a sun halo? Or sun bow?"
One other Stomper called it a "solar halo".
Along with the photo taken by himself, Senior Minister Lee posted on Facebook: "A rare and spectacular sight in the skies above! I am told that this phenomenon is known as a 22-degree halo or a sun halo."
A rare and spectacular sight in the skies above! I am told that this phenomenon is known as a 22° halo or a sun...
Posted by Lee Hsien Loong on Friday 14 March 2025
A sun halo forms when sunlight interacts with ice crystals in the atmosphere. These crystals are from thin clouds so high in the sky that they are made of ice rather than water droplets.
However, a 22-degree halo specifically refers to the ring of light having a radius of about 22 degrees, Professor Matthias Roth, who teaches geography at the National University of Singapore, told The Straits Times.
"As light enters one face of the ice crystals and exits through another, it is bent by about 22 degrees, which accounts for the radius of the halo," said the professor.
According to the National Environment Agency, this is not a common sight in Singapore as sun halos tend to be covered by low to mid-level clouds.
Stomper Kevin shared photos of the rare occurrence above Ngee Ann City at Orchard Road.
A sun halo was previously spotted in Singapore on Sept 22, 2020.
