Shedding light on why a sun pillar shimmers
The sun recently came up over Lingan, Cape Breton, at 6:27 a.m. And now the sun will come up at 7:14 a.m. thanks to Daylight Saving Time.
Maybe that will give more people a chance to admire some of the magnificent sunrises we experience.
Morning skies can be dramatic: at times scarlet, at times ominous and grey. One recent
Sunday, the morning sky was unique. I’m not sure if Nathan Susin planned on capturing a sun pillar when he was
out photographing the early morning light; it’s not easy to forecast the conditions necessary for such a display.
A sun pillar is a narrow column of light that reaches straight up from the rising or setting sun. It forms when sunlight reflects off the surfaces of falling ice crystals. Most times, those ice crystals are associated with thin, highlevel cirrostratus clouds.
The crystals responsible for light pillars usually consist of flat, hexagonal plates. These pretty, plate-like ice crystals fall with a horizontal orientation, gently rocking from side to side as they fall. Their surfaces act as giant mirrors, reflecting light up and sometimes down; the bigger the crystals, the more pronounced this effect will be.
These shafts of light are at their best within a few minutes of sunrise or sunset. They are much more common when arctic air sinks over the region and the necessary ice crystals are plentiful.
When there is arctic air over the region, I hope to have more photos of sun pillars to share with you.
By the way, moon pillars exist as well. A bright moon can create a moon pillar under just the right conditions. On rare occasions, small light pillars may be seen extending above or below a bright planet, such as Venus.
Keep an eye on the sky and your camera handy!