Really seeing the light this week
Thanks to the cloudless skies and extra intense sunlight of July, the blue light on Columbia Street, between 7th and 8th Avenue, has been particularly creepy this week.
Every day of the year that isn’t overcast sees this same patch of electric blue light creep slowly eastward; first over the sidewalk on the west side of Columbia, then over the asphalt of the road and any cars parked along the east side curb. The light then slowly fades away as it creeps forward into the green space of Jonathan Rogers Park.
Such a moving blue light
It’s a startling thing, this light. It paints whatever it touches with a blue that is lately so intensely opaque that you might think you were seeing spray paint — until you saw that the “paint” was ever so slowly moving.
And the source of the mysterious creeping light is not immediately obvious.
It’s from a surprising place, high overhead: two rectangles of deep blue glass mounted along the very top of the fourth storey above the entrance of a building on the east side of the 2900 block of Columbia.
The glass is not a window but rather a decorative parapet feature, backlit by the sun.
The stronger summer sun can really make you see red
The intensity of summer sunlight never fails to amaze me; it’s so much brighter than in the winter.
To provide some idea of the difference, I found this calculation made for Fort Peck in Northern Montana, USA, that shows rhat the amount of energy one square meter of land gets in July is about 160 percent greater than in January.
That’s because this time of year the sun beams as close to straight down on us as it ever will — about 65 degrees at noon in July, versus 19 degrees at noon during January.
That’s why the sun is so much hotter and brighter in the summer, despite the fact that it’s actually about 3.3 percent farther away from us (about 5,007,600 km) that it is during the winter.
Limited edition prints, 50 million years in the making
No one can apparently be bothered to do the horrifically complex calculations needed to determine exactly how long it must take a photon of light to travel from the sun’s core to its surface — maybe 100,000 years, maybe 50 million. It’s enough for science to know that the going is very slow indeed, with all manner of obstacles in a photon’s way.
But once that photon finally reaches the surface of the sun — the photosphere — and clears what you might call the sun’s atmosphere, or chromosphere, then it’s clear sailing and green lights all the rest of the way.
Beyond a shadow of a doubt, you can’t beat sunlight!
Earlier this week I took a photo of the neat shadow striping on an apartment building located just off of Alder Street in the Fairview neighbourhood.
I had read in a book once (and the Internet confirms) that it would’ve taken photons of light some eight minutes to travel from the surface of the sun to the Earth, in order to make those shadows.
It only took me six minutes to ride the seven block distance from Cambie Street in order to take the photo. Click the images to enlarge them.