Tuesday, September 24, 2019
Second day of autumn
Yesterday was the first day of autumn. The autumnal equinox occurred at about 0150 local (Mountain Daylight Time). The equinoxes (vernal and autumnal) are the two points in time and location where the sun appears to be at the halfway point in its twice-yearly N-S (autumnal) or S-N (vernal) journeys through the sky. The equinoxes also mark the two days of each year when the temporal division of daylight and darkness are most nearly equal. The "ends" of the sun's annual journey through the sky are the solstices. The farthest south point and shortest day happen with the winter solstice just before Christmas on the first day of winter. When the sun reaches it's most northerly point on or about June 20, the summer solstice is, you guessed it, the first day of summer. In about 180 days, as the sun retraces its route northward, the vernal equinox will mark the first day of spring and another roughly equal distribution of daylight and darkness.
Of course the sun doesn't really move through our sky. The Earth travels around the sun in an elliptical orbit which takes 365 and a quarter days to complete. As Earth zips around the sun it rotates once every not-quite 24 hours, and our planet rotates around a vertical axis which is tilted about 23 degrees from straight "up and down" which is defined as the plane of the ecliptic, or the plane where on average all of the planets orbit the sun.
The combination of our orbit about the sun and the tilt of our rotating planet is what makes the sun appear to move N-S and S-N throughout the year.
This is stuff we all know, but it's worth thinking about periodically. Many people will stridently tell you otherwise, but it's easy to observe and provides a proof against pseudoscience that we can all enjoy and use to help keep us grounded in a world that sometimes seems to have gone mad.
One of the delights of the day was observing the hawk pictured above. The experten over at iNaturalist have identified it as a Cooper's Hawk, and it may well be, but it doesn't look like one to me. A smallish Accipiter surely, but is it a Cooper's? I'm skeptical but given the fact that I'm no Ornithologist James Simpson, I'm willing to be convinced. Gorgeous bird regardless. And given the perch it took almost certainly a chickenhawk!
Couple of rough autumnal bideos...
This morning I'm going over to the big city (Scottsbluff, Nebraska -- population 15,000) hospital for to have some steroids injected into the areas near some ailing nerve roots. I'm hoping for a significant reduction in pain and a speedy return to normal health and mobility. I will, of course, take what I get.
I hope you're all enjoying the season and blessed with continuing good fortune amid the normal turmoil of life.