Star Gazing

I went star gazing last night. After an eternity of thunderstorms last night was only party cloudy so we did get to see some stuff. There were about a dozen telescopes, refractors, (up to 15") dobsonians and 8" Schmidt-Cassegrains. I saw several objects through a few of them and the views were all pretty comparable. Most had motorized tracking mounts and few were computer guided. It was the first time I saw people type an item into a controller and watched the telescope turn to the object.

The first star we saw was Arcturus a red giant star that's the second brightest star in the northern hemisphere (Sirius is first but wasn't visible). To find it in darks skies, follow the arc of the big dipper's handle and look for the bright star. It's huge compared to the sun, 25x the radius of the sun and about 37,000 ly away. Apparently people have a hard time describing the color. Some see it as reddish others as yellow or champagne or yellow-blue.

But the brightest object in the sky was Jupiter. Through the telescopes we could make out the 4 Galilean moons and see two dark bands across the face of Jupiter. It wasn't in color like in the pictures, but it's very impressive to see.

The second brightest star we could see was Vega (3rd brightest in the northern sky). It's in the constellation Lyra which looks like a parallelogram with an extra star. Vega is only twice the size of the sun and is 25,000 ly away. In the middle of the right side of the parallelogram of Lyra is M57, the Ring Nebula. It's a dying star that's shed it's outer layers so it's donut shaped. It looked like a white smudge and I couldn't really see the dark spot in the middle. In the Hubble it looks like this

M13 is the Great Globulal Cluster in Hercules. There are several hundred thousand stars there and it's about 145 light-years across and 25,000 ly away. I learned that there are very very few metals in M13 (which to astronomers means anything heaver than Hydrogen and Helium). These metal-poor star are known as Population II stars and are old, from when the universe had less metal content.

The double double is a binary star system made of two binary stars. It's in Lyra, to the bottom left of Vega in the above picture. Binary stars are two stars that orbit each other. With a naked eye they might look like just a single star, but with binoculars or a telescope you can (sometimes easily) see that they are two stars. In the double double it's easy to see the two systems, but to separate each one takes a good view and taking a moment to relax your eye and looking just off-center of the star (you're brain puts the two stars together). I could separate one of the systems but not the other.

At the end of the night I saw M31, the Andromeda Galaxy and M32 a dwarf elliptical galaxy next to it. Both looked like white smudges against the black sky. You can't expect things to look like the pictures, but it's cool to see them with your own eyes.