Star Points for July, 2006; by Curtis Roelle Jupiter: Gripped by the Scorpion's Claws

With the occurrence of the Summer Solstice last month we are now headed for the hottest months of the year as the sun beats down. Indeed, in early July the sun is up for nearly 15 hours a day and that's a lot of heat!

In Greek mythology the sun god Apollo used his chariot to carry the rays of the sun across the sky on a daily basis. One day he made the mistake of offering to give his son Phäeton any gift he wanted. The impetuous lad asked his dad for the reins so that he could take his father's chariot for a spin around the block.

Apollo knew that the lad was too young and weak to control the team of mighty horses and was mortal as well. But it was too late, Apollo had given his word. So Phäeton climbed eagerly up into the driver's seat as his Father rattled off the rules of the road and told him to hold tightly onto the reins.

From the moment the horses bolted through the colorful gate of dawn dragging the chariot with its lighter than normal ballast Ph„eton was never in control. To make a long story short Ph„eton's fearful joy ride ended tragically scorching both earth and sky.

While Phäeton was crossing the heavens he saw the heavenly scorpion we know as the constellation Scorpius. It's upraised claws and poisonous tail startled the boy so much that he dropped hold of the reins causing the chariot to tumble toward the earth.

It was told that as the chariot swept near the ground a raging fire erupted drying out the land and creating what we know today as the great Libyan desert. My wife and I were there in the spring for the total solar eclipse and saw for ourselves what a dry and desolate place it really is.

Long ago Scorpius was larger than it is today. We now know the claws as an entirely separate constellation: Libra the scales or balance. The arms of the balance (or claws) are marked by two 2nd magnitude stars with the absolutely marvelous names of Zubenelgenubi and Zubeneschamali.

Currently, the planet Jupiter happens to be entangled in the claws. To locate it step outside as it's getting dark outside and face southwest. Jupiter is the bright star-like object about a third of the way between the horizon and straight overhead.

Jupiter's four brightest moons can be easily seen in the smallest of telescopes. Even steadily held binoculars will reveal its moons.

In 1973 the Pioneer 10 spacecraft passed and photographed the moons Callisto, Europa, and Ganymede, but not Io. Io surprised scientists during a later mission when it was discovered to sport a number of active volcanos.

In small telescopes the moons look pretty much alike. Here are some upcoming opportunities for you to observe and identify them.

On July 4, Independence Day night, Io will be on one side of Jupiter. Lined up on the opposite side in order from closest to farthest from the planet will be Callisto, Europa, and Ganymede.

On the night of the 9th Callisto will be far to one side of Jupiter. On the other side, in order, are Io, Europa, and Ganymede.

Finally, on the night of the 16th all four moons line up on one side of the planet. Closest in to farthest out will be Io, Europa, Ganymede, and Callisto.

Drop me an email and share your any results or troubles you have observing the moons of Jupiter.