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'Rare' upside down rainbow spotted in Wiltshire

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Upside down rainbow spotted over WiltshireImage source, Henry Pawlak
Image caption,

Unlike normal rainbows, the colours are in reverse order with violet on the top and red at the bottom.

A "rare" upside down rainbow has been spotted in the sky over Wiltshire.

The circumzenithal arc, or Bravais' arc, was photographed at Bowood Golf Club near Calne early on Saturday.

Created by sunlight bouncing off ice crystals high in the atmosphere, it is hard to spot inverted rainbows as they appear so high in the sky.

A Met Office spokesman said: "They are seen relatively rarely in the UK but the more defined they are, the rarer they are."

The phenomenon or "smile in the sky" only occurs when thin wispy cirrus clouds - made of ice crystals - are at a specific angle to the sun, according to the Met Office.

'Smiley rainbow'

"Cirrus clouds normally form at between 18,000 and 40,000ft," said the spokesman.

"So circumzenithal arcs appear much higher in the sky and are usually obscured by clouds.

"You have to be in the right spot to see them, so they are rarer to see than rainbows and halos."

Henry Pawlak said he spotted his "smiley rainbow" while playing a round of golf at about 07:15 BST on Saturday.

"It was so unusual and something I've never seen in my 58 years that I thought it was worth taking some snaps," he said.

"They don't seem to hang about for long and we were that early on the course - I don't think there was anyone else around who saw it."

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