Easy astronomy? Deep, profound, cool stuff with no pain? That’s this weekend.
Friday and Saturday night, any time you go out, look up at the sky. The Moon will be surrounded by over a half-dozen bright stars. Of the ten first-magnitude stars in the heavens, eight of them will surround the Moon. And this will be true both Saturday and Sunday nights. So let’s have some fun with this. Grab the kids or your spouse or a girlfriend or a boyfriend and step outside. Here’s a good reason you live in the country.
Look all around the Moon at those bright stars. First, look for color. It’ll take just a few seconds to see that they’re not all white. They’re pastels. So happens, there are no green stars in the universe. But there are light blue and orange stars galore, and this weekend a bunch of those surround the Moon.
The colors tell tales. The bluish ones are the hottest and youngest. The orange ones are the coolest (in the temperature sense). You’ll notice that the star directly below the Moon, meaning the lowest-down of all the stars, is also the very brightest. This blue gem is the famous Dog Star: Sirius. It also happens to be the very closest star we can ever see from New York State.
The orange star to the right of the Moon on Saturday is Aldebaran, in Taurus the Bull. The orange star to the lower right of the Moon Sunday night is Betelgeuse in Orion. But why are they all concentrated in this one area? Look around the rest of the sky and there is no other place that has such a bunch of bright stars gathered together like this.
The reason is that right behind the Moon this weekend is the nearest spiral arm of our galaxy, the Orion arm. It’s a place where there is enough free hydrogen gas that new star formation is active. The center of all this starbirth is Orion, below the Moon. So it’s all very majestic and lovely. And it sure takes our minds away from events in Washington. Whoops, sorry I said that.
Oh, and listen: Many in the media will be calling next week’s Full Moon a Blue Super Blood Moon. Here’s the inside word: It will look no different from any other Full Moon. Really. No total eclipse for us, no Blood Moon, and it won’t look any larger either – except when it’s rising, like every other rising Moon.