Make it a double

Wednesday, October 8, 2014

Since the moon is just past full, and even if we tried, we would not be able to observe any constellations, let us try something else for our viewing pleasure.

First, since what we will be observing is directly overhead, I would recommend a reclining lounge or lawn chair to keep from getting a cramp in our neck from looking directly up.

Next I would recommend a decent pair of binoculars. A pair with a 10x50 rating or at least a 10x35 would work very well. You can use a telescope, if you have one, but just be warned.

Trying to locate something directly overhead might require a trip to the doctor in the morning for sever neck muscle strain.

I don't usually talk about individual stars because they are sometimes difficult to locate, and if we look at an individual star, all we are going to see is a tiny pinprick of light; nothing particularly interesting there at all.

Unless, of course, they are double stars, and in this case I have three of them to look at.

First is the "King of Double Stars." Albireo, the beak star -- and also the brightest star -- in the constellation, Cygnus, the Swan.

If possible, find a place where you will be in the shadow of the moon, that will help a little, then look directly overhead for Cygnus. Albireo is the star at the point of the long body axis where the bird's beak will be.

It is a delightful double in that the component pair are different colors (which binoculars may or may not show). One is a nice golden color and the other is bluish. They are a true double with one located some 377 light years apart and the other 386 light years away.

Next we have a pair which may not be the king of doubles, but it certainly is the crown prince. They are located near Cygnus in the constellation Lyra, the Harp. If you are looking east, Lyra is above Cygnus. If you are looking west, Lyra is below Cygnus.

This double is also near Vega, the brightest star in Lyra and one of the three stars in the Summer Triangle. Find Vega in the binocular field of view, Epsilon Lyrae is the star -- or I should say -- the double star above it (if you are looking west).

Now then, if you do have a telescope and are willing to risk a sprained neck muscle, here is the kicker, Epsilon Lyrae is also called the "Double Double" because each of the pair is also a double star. If you don't want a sprained neck, wait a few weeks when Lyra is closer to the western horizon, then take a look.

If we had a large enough telescope we would discover that are actually 10 stars in that little grouping of stars.

Lastly, a double that may be a little more difficult to find. Its official name is Omicron Cygni and is located back on our old friend Cygnus.

Face north and find Cygnus again, stand so Lyra is on the left as you are looking at it. Draw a line between Deneb, the tail star of Cygnus, and the left wingtip. Located about halfway along that line and slightly below it is our target star, Omicron Cygni.

You might even be able to see the double without binoculars, but with them it is obvious, only this double is not really a double. It is what we call an optical double. they only look like they are close. Actually, they are both along the same line of sight. One is 1,359 light years away and the other is 717 light years away. Still, a nice catch in binoculars.

SKYWATCH: Third quarter moon, Wednesday, Oct. 15. The moon has a close meeting on Saturday, October 11th with Aldebaran, in Taurus, the Bull. Look east about 11 MDT

NEXT WEEK: The coming partial solar eclipse and more astronomical blathering.

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