The days are getting shorter

Wednesday, September 16, 2015

The days have been growing shorter. Ever since the summer solstice where the Sun was as far north in the sky as it gets for the year giving us the longest days and shortest nights; it has slowly been moving back south until on Wednesday, Sept. 23, at 2:21 am MDT it will cross the celestial equator giving us almost equal days and nights -- the autumnal equinox.

Although the equinox is supposed to be the day of equal dark and light, the folks living here on the 40th parallel (the Kansas-Nebraska border) are a little north of the equator so our equal day and night will be on Sept. 26th, and 27th, when we will have 12 hours and two minutes, 11 hours and 59 minutes respectively.

Perhaps you have noticed the days getting shorter and the sunlight shining on the floor through a south-facing window is casting a longer pad of light.

Of course, we astronomers are happy with this situation because shorter days mean longer nights and more for observing time for us.

There are three other astronomical occasions coming up for our enjoyment. First we have International Observe the Moon Night, an occasion to simply get outside and look at the moon which will be celebrated on Saturday, September 19. The moon is almost at first quarter, that means it will look like half a moon high in the southwestern sky.

You won't need anything special to look at the moon, just your eyes. If you have a pair of binoculars, or even a small telescope it will be a help, but the idea is to just get outside and look. The moon is above the constellation Scorpius and the bright star Antares at its heart, the bright dot to the lower right is the planet Saturn.

If you do have a telescope or binoculars, this area is a good one for just looking around, there are star clusters, nebula, and other interesting objects for observation. If you would like more information, point your favorite web browser to "" for a listing of observatories, planetariums, and others who are hosting events that evening.

If you are in the Arvada, Colorado area, I will have my telescopes at the Majestic View Nature Center, so drop on by.

Another event is the return of the Zodiacal Light, the ghostly glow in the early morning sky in the east reaching almost halfway up the sky. Best time to observe is about two hours before local sunrise any time this week up to Sept. 22.

You will need a very dark-sky place, the darker the better and a clear, eastern horizon.

If you can see the Milky Way from where you are, there is a good possibility you will be able to observe the phenomenon.

The Zodiacal Light is sunlight scattered by the bazillion bits of dust particles in the orbital plane of the solar system extending from the Sun out to just beyond Earth's orbit. It is often called a "false dawn" because it gives the impression that the Sun will be rising soon.

It will be a good time too for observing Orion, Gemini, Venus, and other winter constellations.

Our third event will be discussed a little more in detail next week as we get ready for a total lunar eclipse on Sunday, September 27th, so stay tuned.

SKYWATCH: First quarter moon, September 21.

NEXT WEEK: A total lunar eclipse and more astronomical blathering.

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