Wednesday, November 16, 2022

hadn't thought of that

Spotted this piece a couple of days ago, skimmed, bookmarked. But only read it fully, closely today.

From the CBC web site, this is an article on light pillars. Something I've been interested in seeing. I was thinking it'd be fun to experience these, and if lucky, photograph. But I had a hunch that conditions would need to be just so... Could they occur in Ontario?

Apparently, people in Alberta on Nov 10 witnessed these vertical pillars stretching up into the dark sky caused by ice crystals in frigid air.

You need calm conditions. You need cold air, -10°C or -20 or lower. You need bright street lights or building lights.

Similar to parhelia (e.g. sundogs), light gets reflected and forms coloured pillars.

They interviewed Roland Dechesne, past president of RASC Calgary. He said he's seen "light pillars at least a dozen, maybe two dozen, times each winter." Lucky duck.

And then they noted him saying that while they can be pretty, he actually sees them as "a sign of waste."

I hadn't thought of that.

Back to the conditions required I noted above. You need bright lights—aimed upward!


That's light pollution.


Maybe I don't want to see these...

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