Last night an atmospheric optical phenomenon in which a vertical beam of light appears to extend above and/or below various light sources was visible in Weyburn.

Was it an alien abduction? No... it was not.

The effect was created by the reflection of light from tiny ice crystals that are suspended in the atmosphere or that comprise high-altitude clouds.

They are called light pillars (also known as diamond dust when the ice crystals are suspended near the ground) and belong to the family of halos.

However, if the light comes from the Sun (usually when it is near or even below the horizon), the phenomenon is called a sun pillar or solar pillar.

"What's really neat about it is that the structure of the ice crystals is always a hexagon," explained Karen Kennedy-Allin, Physics and Biology Teacher at Weyburn Comprehensive School that also advises the Astronomy Club. "And the faces of the hexagon are always sixty or ninety degrees."

"So even though the light sources are shining forward," added Kennedy-Allin. "Because of the shape of the ice crystals, the light seems to shoot up at ninety degrees from the light source. And what that does, is it causes a bit of diffraction, so we almost see a rainbow of light within those light pillars."

"It was just the perfect mixture of events happening with the cold weather and the ice crystals and the fresh snow that added up to give us that interesting phenomenon," told Kennedy-Allin.

Unlike a light beam, a light pillar is not physically located above or below the light source. Its appearance of a vertical line is an optical illusion, resulting from the collective reflection off the ice crystals, only those of which that appear to lie in a vertical line direct the light rays towards the observer (similar to the reflection of a light source in a body of water).

Of course last night had another phenomenon that occurred, known as the Super Blood Wolf Moon. Unfortunately, due to poor visibility and the ice crystals in the air, the eclipse wasn't visible to most people in our area. And the next full lunar eclipse won't occur until May of 2021.

Kennedy-Allin and the WCS Astronomy Club had planned to view the event last night, but were sadly unable to do so.

"It wasn't really cloudy, but the ice crystals in the air just distorted the view completely of the moon," Kennedy-Allin explained.

For those interested in celestial events:

  • There will be a Supermoon on February 19, 2019
  • A Total Solar Eclipse on July 2, 2019
  • A Partial Lunar Eclipse on July 16, 2019
  • And an Annular Solar Eclipse on December 26, 2019

Light Pillars 2