White Rainbow

The rare phenomena, named a fog bow, was spotted by Sam Dobson as their ice breaking ship cruised through the chilly waters of the North Pole.

Says the 51-year-old amateur photographer from Russia, 'It was around midnight, but because of the time of year it was still fairly light. 'At first it just looked like a cloud, but as we got closer it was a solid rainbow, but white.'

A fog bow is a similar phenomenon to a rainbow, but it appears as an arch in fog rather than rain. And because of the very small size of water droplets that cause fog, smaller than 0.05 millimetres, it appears as a white arc, rather than a multi-coloured one.