In his Book of Problems, Aristotle asked, “Why is it that one sneezes more after one has looked at the sun?”
It’s known as the photic sneeze reflex.
The phenomenon largely remains a mystery. The scientific name for a photic sneeze reflex is Autosomal-dominant Compelling Helio-Ophthalmic Outburst syndrome. Quite a mouthful that is rather aptly shortened to ACHOO syndrome!