Singaporeans were treated to a spectacular celestial display on August 25, 2025, as a rare sun halo graced the skies above the island nation. The captivating phenomenon, characterized by a luminous ring encircling the sun, was visible across various locations including Clementi, Paya Lebar, Pasir Panjang, and North Bridge Road, sparking widespread awe and social media sharing.
This ethereal optical event occurs when sunlight interacts with ice crystals present in high-altitude cirrus clouds. These crystals refract, or bend, the light at approximately a 22-degree angle, creating the distinct circular appearance of the halo. Professor Matthias Roth from the National University of Singapore explained that this specific angle of light bending through the ice crystals accounts for the halo's radius.
While visually stunning, the National Environment Agency (NEA) and other experts remind the public that observing the sun directly, even with a halo, requires protective eyewear to prevent eye damage. Sun halos are not a frequent occurrence in Singapore, primarily due to the country's typical cloud cover, which often consists of lower and mid-level clouds. The formation of halos necessitates the presence of high-level, ice-filled cirrus clouds, conditions that are less common in Singapore's tropical climate.
The last recorded sighting of a sun halo in Singapore was on March 15, 2025, making the August 25 event a particularly noteworthy occasion. The widespread sharing of images and videos of the sun halo across social media platforms, including TikTok and Facebook pages like The Photographic Society of Singapore, highlights the public's fascination with such natural occurrences.
Netizens encouraged others to witness the spectacle, often advising the use of sunglasses for safe viewing. This shared experience fosters a sense of community and collective appreciation for the beauty of atmospheric phenomena. The appearance of the sun halo serves as a beautiful reminder of the intricate workings of our atmosphere, underscoring how specific atmospheric conditions can create these mesmerizing visual displays and spark curiosity about atmospheric optics.