A sun pillar is an atmospheric phenomenon resulting from sunlight reflecting off falling ice crystals in cirrostratus clouds to produce an apparent vertical column of light. It is a rare sight because a number of atmospheric conditions must be present at the same time. As it happens, Torontonians have been able to witness this spectacle at least a few times in the last two years. Here is an occurrence seen in January, 2021 at the Humber Bay Arch Bridge, with the pillar reflected on the frozen mouth of Humber River.