A rare ‘fire rainbow’ formed in the skies of Singapore on Monday for just 15 minutes.
The incredible ball of multi-coloured light formed ‘out of nowhere’ behind a cloud on Monday afternoon in North-East District, Singapore.
It was so bright that onlookers even mistook it at first for a UFO as it loomed ominously across the skyline.
Fire rainbows – also known as circumhorizontal arcs – are a rare occurrence caused by light bursting through cirrus clouds at high altitude.
The sunlight is reflected through the ice-crystal clouds into a bright prism of colors.
Pet stylist Bernard Ong, who recorded a clip of the fire rainbow, said: ‘I have never seen such a beautiful Mother Nature before. This was totally something amazing.’
‘It was quite bright,’ he added. ‘Someone said it looks like a UFO, too.”
Onlooker Natalie Claudia Wong also captured the fleeting rainbow on her phone at around 5pm before it disappeared just 15 minutes later.
HOW DO FIRE RAINBOWS FORM IN THE SKY?
The phenomenon was first dubbed a ‘fire rainbow’ back in 2006, when one was spotted by a Washington journalist.
And meteorologist Justin Lock told 14 News that a strict set of conditions are required for such phenomena to appear.
They only occur in high-level cirrus clouds, which usually form at about 18,000ft. They appear thin and wispy and are made up of tiny ice crystals.
‘To produce the rainbow colours the sun’s rays must enter the ice crystals at a precise angle to give the prism effect of the color spectrum,’ Lock said, adding the sun must be at an altitude of at least 58 degrees above the horizon.
The same sort of thing occurs when we see coloruful sunsets.
In those instances, high-level cirrus clouds produce many colours due to the sun’s low angle, meaning that we see reds, oranges and purples.
Student Wong, 23, said: ‘I was walking towards my bus stop when I found myself in awe of this beautiful cloud and the myriad of colours that were bursting out of it.
‘This was the most beautiful thing I’ve ever seen, and I literally turned on Facebook Live to share the exact moment that I saw it.
‘I was feeling pretty down over the past week, but this immediately lifted my spirits.’
Because such a specific angle is necessary for the colours to be visible, the phenomenon is most common at middle latitudes.
‘You’re more likely to see this type of rainbow during the summer in North America,’ Dayna Vettese, a meteorologist at The Weather Network, told two years ago. ‘But in places like Europe, the arcs are much rarer.’