The 'Evening Star' and the 'Ringed Planet' will be close to each other in the southwest sky after sunset

By Jamie Carter
December 06, 2019
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On a clear night, you can’t miss the brilliant planet Venus. It’s shining brightly in the southwestern sky after sunset each night this month, and on Tuesday December 10, it’s joined by everyone’s favorite, the ringed planet Saturn.

This is the second time that Venus and Saturn have appeared next to each other in the night sky in 2019. Back on January 22, the same thing happened before sunrise. Sunday’s event will be much more convenient to see, and all you have to do is look to the southwest.

When will Venus and Saturn appear closest together?

The moment when two planets appear to be closest to each other is called a “conjunction." That happens on Tuesday after sunset, though the two brilliant planets will be close enough to impress stargazers for a few days before and after.

According to When the Curves Line Up, Venus will be just 1.8° to the lower left of Saturn on Tuesday during twilight. That’s less than the apparent size of two full moons. Although they’re closest on Tuesday, they’ll be only a fraction further apart at a mere 1.9° on Wednesday night. However, before Tuesday, and from Thursday onwards, the two planets will seem much further apart.

How can you see Venus and Saturn at their closest?

Venus and Saturn will be visible relatively low in the sky—just 11° above the horizon—so find yourself an observing position that has a good, clear view of the southwestern horizon. The second floor of a building should be fine, as long as there are no trees or other buildings blocking your view. You won’t need a telescope or binoculars to see the celestial sight because both planets are bright enough to see with your naked eye. However, if you want to see the incredible sight of Saturn’s rings, you'll need a small telescope.

Why do Venus and Saturn appear so close?

Tuesday’s conjunction is actually little more than an illusion caused by the planets' positions in the solar system. Saturn is an outer planet, and it takes 29 years to orbit the sun. Venus takes just 225 days to do the same. Venus is presently "catching up" with Earth, and as it races clear of the sun, it appears to get between Earth and slow-moving Saturn. You can get a great ‘live’ view of the solar system on The Planets Today.

How close are Venus and Saturn?

The planets aren't close together at all, it’s just a line-of-sight illusion. This week they’re over 800 million miles apart, while Venus is about 25 million miles from Earth. So when you’re watching Venus and Saturn pass closely in the early evening night sky, remember that you’re much, much closer to Venus that it is to Saturn.

Why is Venus called the ‘Evening Star’?

Venus often gets mistaken for a star (and frequently for an UFO) because it’s so bright. That’s because its cloudy atmosphere reflects the sun’s light, but also because it’s relatively close to us, so it naturally looks brighter than any other planet could. Since Venus is an inner planet, and orbits the sun much more closely than Earth does, we only ever see it either close to sunrise or for a short time after sunset. It doesn’t get far enough from the sun, from our perspective, to be visible all night. For a few months each year, it's only visible before dawn, so we call it the "Morning Star." When it's only visible just after dark—shining brilliantly as it is now—we call it the "Evening Star."

If there are clear skies, take a look at the southwestern sky after sundown this week to see brilliant Venus and Saturn close together, before the two planets gradually move further apart and continue their lonely journeys around the sun.