StarDate

Morning Venus


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If you step outside at dawn on June third of 2033, you’ll see the planet Venus standing due east – the brilliant “morning star.” But if you don’t want to wait that long to experience that beautiful view, then take a look at dawn tomorrow – Venus will be standing in the same spot in the sky. Not only that, it stands at that spot in the sky every eight years.

In fact, anytime you see Venus – whether as the morning star or evening star – you can find it at that same spot eight years later. That’s because there’s a near-“resonance” in the orbital cycles of Earth and Venus. Venus completes 13 orbits around the Sun for every eight orbits that Earth makes. The ratio isn’t exact, but it’s quite close.

Thanks to that, Venus follows five repeating cycles across our sky. It’s like the planet is a toy train on a looping, winding track. It hits every point along the track with every cycle. If you plot that motion from the perspective of Earth, it traces out a flowing pattern like five rose petals.

The clockwork precision makes it easy to predict the entire sequence of Venus’s appearances. We know that it always remains in view in the morning sky for about 263 days, disappears for about 50 days, then moves into the evening sky.

So if you miss the view of Venus tomorrow, or the next day, or the day after that, just mark it in your calendar – and look for it in the same location eight years later.

Script by Damond Benningfield

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StarDateBy Billy Henry