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Moon and Saturn

July 25, 2015

The stately planet Saturn accompanies the Moon across the sky tonight. It’s close to the lower left of the Moon at nightfall, and looks like a bright star. As a bonus, the bright orange star Antares is close by as well, farther to Saturn’s lower left.

Saturn is the sixth planet out from the Sun — more than nine times farther from the Sun than Earth is. It’s also big and bright, which makes it the most distant planet that’s easily visible to the unaided eye. The combination earned Saturn a special place in ancient skylore.

Saturn takes almost 29-and-a-half years to complete one orbit around the Sun. So as seen from Earth, it takes that long for the planet to complete one full turn against the background of distant stars. That compares to only about two years for Mars, and about 13 years for Jupiter.

Because of this leisurely progression across the sky, several cultures associated the planet with powerful and stately gods. The ancient Assyrians, for example, named it for a god known as “the oldest of the old.” In Greece, it was named for Cronus, who was the father of Zeus, the king of the gods of Olympus. And the Romans adapted Cronus as Saturn, the god of agriculture.

Saturn will slowly pass by Antares over the coming months, and start to really pull away late next year. After that, it won’t return to the vicinity of the scorpion’s heart until the year 2044.

We’ll have more about this beautiful evening grouping tomorrow.

Script by Damond Benningfield, Copyright 2015

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