Orion

What a night for stargazing! Perfectly clear. The half-moon obscured some of the sky with its bright light, but the constellation Orion showed up clear half-way up the eastern sky when I went outside with the binoculars ten minutes ago.

Orion is very identifiable, at least its main five stars, which actually make up a small part of the entire constellation. Three bright stars in a perfect row form Orion's belt. On either side of the belt are two bright stars, directly opposite each other, in near perfect symmetry. One is red, the other blue. You can detect the colors with the naked eye.

Betelgeuse, the red star, is 450 light years away. It is huge, so huge that it would stretch out to the orbit of Jupiter if its center were at the sun. And it is about to explode. Every night, astronomers look up to see if Betelgeuse is still there. We would know if it exploded--the last supernova happened in 1054, and lit up the sky with a glow so bright that it was like daylight for about a week. Many cave paintings, legends, and myths record the event.

Of course, Betelgeuse could have already exploded--say, 449 years ago. We just wouldn't know it yet.

Opposite Betelgeuse is Rigel, a blue star, one of the brightest in the sky.

But the most interesting part of the Orion constellation is found below the belt, in the sword which hangs towards Rigel. To the naked eye, there appear to be three stars in the sword. They are quite dim. However, if you look at the middle star with binoculars, you find that it is more a blue-green blur. It is the Orion nebula, an enormous cloud of gas. Within in the cloud are thousands of stars.

Last winter I saw a close-up of the Orion nebula through a telescope, and it was one of the most beautiful things I had ever seen. Tonight, I saw the green glow through the binoculars for the first time since that night last winter. Binoculars give you a better view of the entire nebula, since it is actually about the size of the moon in our sky.

While Orion shown to the east, the constellation Pleiades showed dimly straight overhead. Pleiades looks like a mini Big Dipper, and is often mistakenly called the Little Dipper. The real Little Dipper is connected to the Big Dipper up north--Pleiades, however, is directly overhead, at least in the winter at about 10 pm. It is a mere blur to the naked eye when it is anywhere but directly overhead, where there is less atmosphere to interfere with our vision. It is the star cluster Tiffany spotted two nights ago as detailed in the entry below. At that time, it was halfway down the eastern sky, and more difficult to spot.

The naked eye can discern at most seven stars in Pleiades. But with a binoculars, the number grows to at least two dozen, and they are bright. In actuality, Pleiades is a cluster of more than 100 stars, all in close proximity to each other. Therefore, Pleiades is the rare constellation where the stars don't just appear to us here on earth to be near each other, but actually are in the same neighborhood of our galaxy.