Trego's Mountain Ear

As snow blankets my part of the world in the beginning of Winter, I begin the wait for the solstice – the shortest day. Technically, this year the solstice occurs on Thursday, December 21, at 8:27 pm (in Eureka). On the 21st, the sun will rise at 8:30, and at 8:31 on Friday the 22nd – but on Friday sunset is a minute later – 4:46. The change isn’t sunrise, it’s sunset.

Our shortest day is 8 hours, 14 minutes and 37 seconds. By year end dawn will be 3 minutes later, and sunset 7 minutes later. And, winter officially starts with the solstice – the snows and freezing temperatures before that are Christmas tree season up here. The days will grow longer until June 21 – when the day length reaches 16 hours, 11 minutes and 4 seconds. And on that note, summer will officially begin.

Twilight was never absolutely clear – but when you realize that there are three types of twilight, it becomes a lot easier. Civil twilight is basically a time when you can still see the sights – from sundown to where the sun is 6 degrees below the horizon. Nautical twilight has the sun between 6 and 12 degrees below the horizon – and you can see both the horizon and stars.

Astronomical twilight has the sun between 12 and 18 degrees below the horizon – still too much light for astronomers to view the dimmer stars.

And after astronomical twilight comes night. We get a lot more night at the winter solstice than the summer solstice.