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Stationary Saturn

StarDate: 
April 16, 2018

The word “planet” comes from a Greek word that means “wanderer.” The title was bestowed because, over time, each of the bright planets moves against the background of “fixed” stars.

Occasionally, though, a planet stops wandering and stands still against that background — it’s stationary.

The planets Mercury and Saturn both reach such a standstill this month. For a while, each will move in sync with the surrounding stars, like members of a band marching in a parade — the result of our changing viewing angle.

Saturn, for example, spends most of the year moving from west to east across the stars. But Earth follows a smaller orbit around the Sun. So once every 13 months, our planet passes Saturn and pulls ahead of it. As it does so, the viewing angle changes, causing Saturn’s position against the stars to shift. When the angle is just right, Saturn appears to stop moving at all.

And despite what astrology tells us, there is no cosmic significance to Saturn or any other planet standing still. It’s part of the eternal cycle of the planets as they “wander” across the night sky.

Look for Saturn standing almost due south at first light. It looks like a bright golden star, with the orange planet Mars close to the lower left. They’re above the “teapot” outlined by the stars of Sagittarius. Over the coming days, Saturn will maintain its position relative to those stars, while Mars moves away from them, eastward across the starry background.


Script by Damond Benningfield

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