Sunday 17th August 2025

Having spent the day exploring Porto, Portugal, Nigel Donovan (Member 7,165) spotted a sun pillar that appeared to shine up from the centre of the city into the evening sky above. It was the result of light from the low Sun reflecting off the undersides of the tiny ice crystals in the high Cirrostratus fibratus clouds. ‘It fully matched the wonder of the towers of Porto that we had visited during the day,’ said Nigel.




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