Winter solstice arrives on Monday

The winter solstice is upon us. Monday, the first day of winter, is also the day we start gaining daylight once again.

This time of year the sun takes a very low arc across the southern sky, rising in the southeast and setting in the southwest, and not spending more than 8½ hours above the horizon at this latitude.

Monday’s the day that the sun reaches its lowest point in the southern sky. This low sun angle means that we’re not getting nearly the amount of solar power and radiation that we get in the summer.

From now through late in June the sun’s arc across the heavens will get higher and higher and we’ll eventually get warmer. However, the coldest weather of the winter is yet to come.

Blame it on the North Polar regions. There’s been little or no sun up there for some time now and super cold air has built up. The general circulation of the global winds causes the cold air to spill our way in intervals until early March.

The sun’s daily path is a reflection of the Earth’s daily and annual motions. Since you were a little kid you’ve known that Earth’s rotation causes the sun to rise in the East and set in the West.

The Earth’s orbit around the sun also affects how we see our home star in the sky, because the Earth’s axis is tilted to its orbit around the sun by a 23.5 degree angle.

On the day of the winter solstice the Northern Hemisphere of the Earth is tilted at the maximum angle away from the sun’s most direct rays. The noontime sun is shining directly over the latitude line called the Tropic of Capricorn, which lies 23.5 degrees in latitude south of the Earth’s equator.

In the Everett skies the noontime angle of the sun will be as far south as it can be in our sky at 18.5 degrees above the horizon.

Six months later, on June 21, the day of the summer solstice, we’ll be on the other side of Earth’s orbit around the sun and the Northern Hemisphere will be basking in the sun’s most direct rays. The sun will take a long, high arc from the northeast to the northwest horizon.

On the day of the summer solstice the noontime sun is at its farthest northern point in our sky at a high 65.5 degrees above the southern horizon.

After summer solstice everything goes in reverse: The sun’s path gets lower and lower and the days get shorter and shorter.

Ancient and not-so-ancient cultures were keenly aware of the sun’s annual cycle and many of them worshiped the sun.

In fact, there was a lot of sun worshipping going on in Northern Europe. Ancient observatories like Stonehenge in Great Britain and the cavelike Newgrange in Ireland are examples of this.

It’s no accident that the early Catholic Church established Dec. 25 as the day that Christ was born. No one really knows the exact date of Christ’s birth, but one of the reasons the church chose Dec. 25 was to battle against the great pagan celebrations that occurred around the time of the winter solstice, when the sun was “reborn” and started its upward climb into the sky.

Special planet news: Over the next week or so you can use the bright planet Jupiter in the low southwestern evening sky to see Neptune, the most distant planet in our solar system.

Neptune is just to the upper right of Jupiter, less than a half-degree away from the largest planet in our solar system.

Just take a small telescope or a really good pair of binoculars and see if you can see a little bluish green dot to the upper left of Jupiter. That’s Neptune, more than 2.8 billion miles away from Earth.

The new crescent moon will be just to the lower right of Jupiter and Neptune, and on Monday night the moon will be just to the upper right of the planet pair.

If you’re up really late at night, you can see the bright planet Mars rising in the east. It’s the brightest starlike object in that part of the sky right now and has a reddish tinge to it.