Published: December 2006
Did You Know?
In Did You Know? the National Geographic magazine team shares extra information we gathered to expand your knowledge of our featured subjects.

Finding Saturn's Ears

To the ancient Greeks who observed the heavens, Saturn was one of six "wandering stars," which, over the course of a year, seemed to move forward and backward against the fixed background of stars. Two thousand years later, still trying to understand these mysterious bodies, which we now know as planets, Galileo pointed his primitive "optical tube" toward Saturn. What he saw in 1610 confounded him. He thought he saw an object made of three stars—a large disk with two small globes touching each side. In 1612 he noted that the "companions" had vanished, but after they reappeared in 1613, Galileo wrote that Saturn had "ears."

Four decades later the magnifying power of telescopes had improved enough that Dutch astronomer and physicist Christiaan Huygens recognized the "ears" as the planet's ring system, one of the most magnificent sights in the night sky. Today, anyone with a modest telescope—even a good bird-watcher's spotting scope or a powerful pair of binoculars on a sturdy mount—can discern Saturn's rings from a dark backyard.

Saturn is poised for viewing on these cold December nights. Early in the month, depending on where you live in your time zone, Saturn will be fairly high in the eastern sky by 11 p.m. (in northern temperate latitudes). It will be a bright and steady pale yellow dot; below Saturn, separated by a span smaller than the width of your fist at arm's length, will be the twinkling blue-white star Regulus in the constellation Leo. Later in the month, Saturn will rise earlier and shift toward the southeast. Saturn will remain high in the southwest sky as dawn approaches, with Regulus to its left.

To see the rings as more than a fuzzy blob around the planet, and to see the dot that is its huge moon Titan, you will need a telescope or binoculars that magnify at least 20 to 25 times, and your scope must be very steady. Details of when, where, and how to find Saturn (and other planets) can be found in monthly magazines such as Sky and Telescope. Don't expect a view like those from the Hubble Space Telescope or the Cassini spacecraft now orbiting the planet. But a mere glimpse of Saturn and its wide expanse of rings can be magical.

—Barbara L. Wyckoff