July 3, 2013
BY DAVID WARD
July is a great time to look for the constellation Scorpius the scorpion, one of the few constellations that actually looks like what it is supposed to. On one of our balmy summer evenings look low in the southern sky for a fairly bright orange-looking star. That is Antares, the heart of the scorpion. His head is to the right, marked by three dimmer stars almost in a straight line. Follow his body down and to the left where it makes a hook. If you can see far enough to the south you might even see its stinger, marked by the star Shaula.
Scorpius depicts the tiny scorpion that stung and killed the famous hunter Orion. In the sky it is huge, much larger than Orion himself. Orion, perhaps like a lot of other hunters, was quite boastful, bragging that he could hunt and kill any beast on the face of the Earth.
The gods had a low tolerance for boasting by puny humans and even though Orion was part god, being the son of Poseidon, they sent a scorpion to fell the mighty Orion. Both the hunter and the scorpion were placed in the sky but out of respect for Orion’s pride, they occupy opposite sides of the sky so the two are never seen together.
The Chinese see this grouping of stars as the “Azure Dragon,” a powerful but friendly creature rising from a river to bestow wisdom and happiness on humankind. The Hawaiians saw these stars as a giant hook that the Polynesian superhero, Maui, used to pull the Hawaiian Islands out of the ocean.
The scorpion has claws also but they were borrowed to create another constellation, Libra, the scales, a long time ago. To the west of Antares, look for two stars out by themselves about a fist width apart. Their names are Zubenelgenubi and Zubeneschamali, which mean the southern and northern claws of the scorpion in ancient Arabic.
That bright orange-looking star is one of the largest stars we can easily see with our naked eye. It is swollen up in its old age to a size millions of times larger than our sun. If our sun were in the middle of that star, Mercury, Venus and Earth would all be inside of Antares. Its name is from Greek and it means “rival of Mars” because of its red or orange color.
Scorpius is one of the 12 constellations of the Zodiac which circle the globe and through which the sun, moon and all the planets travel because all the major bodies of our solar system lie in the same plane. The sun spends less time in Scorpius than in any of the 12, only about seven days.
The Milky Way galaxy, our home in the vast cosmos, lies just to the left of the southern part of the scorpion. Scan that area with binoculars some clear dark night to find lots of glittering star clusters and glowing clouds of gas.
Two bright planets are out in the early evening in July. Look for Saturn glowing with a yellowish color to the right of Antares. Venus is hanging low in the west, a brilliant light in the sunset glow.
Look for the moon very close to the bright star Spica, right of Saturn, on the evening of July 15. The next night the moon will be below Saturn.
On July 5 our little planet is its farthest from the sun and moving at its slowest in our yearly journey around the sun. If you are wondering why it is summer now, it is because our seasons are caused by the tilt of the Earth, not by its distance from the sun.