Well, according to National Geographic, light pillars are vertical columns of light that form when artificial or natural light bounces off the faces of ice crystals floating relatively close to the ground.
According to the University of Illinois' Weather World 2010 project, these ice crystals typically fall horizontally to the ground and have hexagonal plate-like shapes.
This phenomena was recently observed in Ohio.
See the National Geographic article on light pillars here. You can also check out the University of Illinois' Weather World 2010 project where it covers light pillars here.
WKYC News
