Saturday, September 16, 2017

Sunset

Around 2:30 p.m. I and Indy went out onto the deck to read. (Well, I was the only one who did any reading.) I was expecting the southeast side of the deck to have a nice bit of shadow to sit in but there wasn't any. Funny, I remember sitting out there about this time just last month and the deck would be half in shadow. Thought about it and decided it's September. The sun's rising and setting points on the horizon change most dramatically right around the equinoxes. During the Autumnal Equinox the sun will appear to rise and set further to the south than during the summer. Therefore, because of the way my house is situated, the deck stays in full sun longer during the daylight hours. The effect will last until Winter Solstice.  (Of course, the kicker is "during daylight hours" which grow shorter.)    -     The temps have been in the 80's for a couple of days so Indy and I put off our last walk until well after sunset. Showers are predicted for tonight but it was only cloudy when Indy and I took off. We'd done the same thing the night before when the sky had been clear. Last night I could barely make out the path and Indy was just a black mass moving against a gray background. Tonight it seemed much lighter and I could see clearly. The moon wasn't up yet on either night. Why would it appear lighter on a cloudy night than on a clear night? Pretty sure it's partly about light pollution from nearby population centers reflecting off the clouds and partly because of light rays from the sun - which though it is below the horizon - being bent due to changes in the refraction index of the air by thermal variations. Maybe it is more proper to say 'It was a light and stormy night.'

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