The Ellensburg sky for the week of 8/31/13

Saturday: Geometry review: part 3. School starts this week so it is time to continue our little geometry review from last week. Did you forget last week’s lesson? Well, go to the litter box, dig out last Saturday’s paper and review it. Then go outside at 9 p.m. with notebook in hand. Ready? A square is a quadrilateral with four sides of equal length and four right angle corners. A good example in the sky is the Great Square, an asterism (group of stars) consisting of three stars from the constellation Pegasus and one star from the constellation Andromeda. At 9 p.m., the bottom of the Great Square is two fists held upright and at arm’s length above due east.

Sunday: There is a lot to see at the Kittitas County Fair. But there is not a lot to see in the sky when you are at the fair because the fair lights, which are fairly bright, obscure most celestial objects. The bluish star Vega is one of the few objects bright enough to be seen. As you are finishing your rides at 10 p.m., look for Vega nearly straight overhead.

Monday: Labor Day was the brainchild of labor unions and is dedicated to American workers. The first Labor Day was celebrated in 1882. The Greek mythical hero Hercules probably wished there was a Labor Day to commemorate his work. As punishment for killing his family while he was temporarily insane, he had to perform twelve nearly impossible tasks such as killing monsters or stealing things from deities. Humm. Maybe we shouldn’t commemorate his labors. But we can enjoy his constellation. The keystone asterism representing the body of Hercules is six fists above the west horizon at 10 p.m. For more information about the Labors of Hercules, go to http://goo.gl/ozVF5.

Tuesday: Friday: “I’m a little teapot, short and stout. The galactic center, I pour it out.” (I’m a Little Teapot, astronomy version, 2013.) Despite its great size and importance, the center of our Milky Way galaxy and its giant black hole remains hidden to the naked eye behind thick clouds of gas and dust. By plotting the orbits of stars near the middle of the galaxy, astronomers have determined that the black hole’s mass is equal to about 4.5 million Suns. While you can’t see the actual galactic center, you can gaze in the direction of the center by looking just to the right of the teapot asterism in the constellation Sagittarius. This point is about one fist above the south-southwest horizon at 9 p.m.

Wednesday: The calendar says summer is nearing an end. School starting today says summer is nearing an end. The summer triangle in the sky begs to differ, as it is still high in the sky. Vega, the brightest star in the triangle, is a little bit west of straight overhead at sunset. Deneb is a little bit east of straight overhead and Altair is five fists above the south horizon.

Thursday: Start thinking about saying good-bye to the evening planets. At 8 p.m., Venus is about a fist above the west-southwest horizon and Saturn is one and a half fists above the southwest horizon.

Friday: Start saying “Good Morning” to Mars and Jupiter. (Or “God Morgen” if you thing the planets speak Norwegian.) They have been out for a while but now they are high in the sky at 6 a.m. Jupiter is four and a half fists above the east-southeast horizon and Mars is three fists above the east horizon.

The positional information in this column about stars and planets is typically accurate for the entire week. This column is also available online at http://theellensburgsky.blogspot.com/.