December 21, 2010

December 21, 2010 - 23:28

Axial tilt is the Reason for the Season

Earth's seasons are the result of the 23.5 degree tilt of the planet's axis. Half of each year the southern hemisphere has more exposure to the sun than the northern hemisphere, and the other half of the time the reverse is true. On one day of each year the sun reaches its maximum elevation and produces the largest number of daylight hours. This day is called the summer solstice, and in the northern hemisphere it usually falls on 21 June.

When the opposite set of circumstances occurs, with the Sun is at its lowest elevation and daylight hours at their shortest, this is the winter solstice... the first day of winter. That is today.

Today, several hours before the solstice, is marked by a very rare total lunar eclipse. The last time a total eclipse coincided with the solstice was in 1638. The next will be in 2094. Volcanic ash in the atmosphere, we are told, should cause the moon to take on a eerie orange glow, which to some degree it did.

We had a few thin clouds partially obscuring the show, but I still managed a few not so good photos. I need better equipment for shoots like these.

This year's event is also supposed to coincide with the Ursids meteor shower, so in a way we get a three-fer.

With or without the celestial light shows, this day and this time of year are traditional for celebration. I would like to wish and/or hope you had/have a festive, merry and productive nonspecific day of your choice for fall/winter celebration. You may choose from any of the following, listed in no specific order.

There. Does that cover everyone? If not, mea culpa. I'll strive to do better in 2094.



Labrys said... mea culpa required! We had a wonderful night feast, lit the Yule log and went outdoors to watch the moon achieve total darkness. Then the normal Pac Nor'west re-asserted itself, clouded up and rained on us. So indoors we went for a few hours...but I got to see an unclouded finish. It was a lovely night...Happy New Year to you, too! I am watching the Hogfather today!