In June, I wrote about the Great Summer Arc. If you follow the handle of the Big Dipper southwest, you will see the bright star Arcturus. Then, farther southwest near the horizon, you will see the star Spica. The Great Summer Arc is still there, but is farther west now. The bright star in the west-southwest, just above Spica, is Saturn. It will set at 10:05 p.m. tonight. Mars, just to the left of Saturn, will set at 10 p.m. Jupiter will rise in the east at 12:12 a.m. and Venus will rise at 2:35 a.m.
In addition to the Great Summer Arc, the Summer Triangle is a wonderful sight and consists of three very bright stars: Vega, Deneb and Altair. The best way to see the summer triangle is to simply sit back in a chaise lounge chair in the backyard and look straight up after dark.
Vega is located directly overhead in the constellation Lyra. In fact, it will be one of the first stars you’ll see as the sky darkens around 9 p.m. in Central Oregon. It is the fifth-brightest star in the heavens and is only 25 light years distant.
Deneb is the tail of the constellation Cygnus, the Swan. In fact, the Arabic word for “tail" is Deneb. It is located northeast of Vega and is the 19th-brightest star. Deneb is a blue-white giant with a mass 20 times greater than our sun. The distance remains a mystery, but is believed to be about 3,200 light years.
Altair, in the constellation Aquila, is the 12th-brightest star. It is 1.8 times the mass of our sun, and 11 times brighter at almost 17 light years distance. Altair is southeast of Vega and completes the triangle.
Central Oregon and many other locations around the world will also be treated to two full moons this month. The first one was on Aug. 1; the second will be on Aug. 31. When there are two full moons in one month, the second is called a blue moon.
