Summertime Skies
Jim Craig, James H. Lynn Planetarium
Shorter nights mean less time for stargazing but the warm weather is a great compensation. Summer is a great time for taking out a lawn chair, lying back and enjoying the night skies.
Throughout the summer, look high overhead for three bright stars that form the Summer Triangle. Starting with the northwest star and moving counterclockwise, they are Vega, in the constellation Lyra, the harp; Altair,in Aquila, the eagle; and Deneb ,in Cygnus, the swan.
The Milky Way stretches across the sky. In clear skies, it will look like a high, faint band of clouds. This cloud is made up of about 200 billion stars that form our home galaxy. Scan along the Milky Way with binoculars to see star clusters and faint, wispy clouds of gas where new stars are formed.
In the southern sky, look for a long line of stars that form the body and tail of the constellation Scorpius. Unlike many constellations, this one really looks like its name.
Within Scorpius, you'll see what looks like a very bright star. This is the planet Jupiter. A telescope or even a good pair of binoculars will show you up to four of Jupiter's moons. You can watch them change positions over a period of hours. In 1610, Galileo observed these moons and used it as proof that the earth wasn't the center of the universe.
Before dawn, look almost due east for the planet Mars. Mars has a distinct reddish-orange color and there aren't many bright stars in its vicinity. Right now, Mars isn't much to look at through your telescope, but as we enter autumn, the earth will swing to the same side of the sun as Mars, providing a better view of the red planet.
On Aug. 12, the Perseid meteor shower makes its annual appearance. The best viewing is after midnight when our part of the atmosphere is turning into the meteor stream. It's hard to believe that these bright streaks of light are caused by small bits of comet debris usually no bigger than a pencil eraser. Expect to see 50 or more meteors per hour.
Toward the end of August, look in the early mornings for the brightest star in the sky, Sirius, to make its seasonal debut. It will be a dazzling blue-white color in the morning twilight. Ancient people used Sirius to let them know that summer was ending and that they needed to prepare for winter. Because Sirius is in the constellation Canis Major, the large dog, it's also known as the Dog Star. When it makes its morning appearance, we call that time of year the "dog days of summer."
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