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Venus and Saturn

January 20, 2023

The diversity of the planets in our own solar system is amazing. They range from bare rocks roasting in the sunlight to giant balls of gas with monster storms churning through their skies.

Consider Venus and Saturn, which are staging a close conjunction in the early evening sky. Venus is about the size of Earth, and its atmosphere is hot enough to melt lead. Saturn is almost 10 times wider than Earth, and its atmosphere is stretched into globe-circling bands by Saturn’s high-speed rotation.

Venus is the second planet out from the Sun, so it receives a lot of sunlight. Its atmosphere is made mainly of carbon dioxide, and it’s about 95 times thicker than Earth’s atmosphere. That traps a lot of solar energy, heating the surface to more than 850 degrees Fahrenheit.

Saturn is the sixth planet from the Sun. It receives much less sunlight, so its atmosphere is cold. But it generates a lot of internal heat — more than it gets from the Sun. That powers storms that roll through its bands of clouds. And every few decades, it produces a monster storm that’s as big as Venus, and can eventually wrap around the entire planet.

Look for Venus and Saturn quite low in the west-southwest in the early twilight. Venus is the “evening star.” Tonight, Saturn stands a little above it. They’ll be closer tomorrow evening, and appear to almost touch each other on Sunday — a close pairing of quite different siblings.

Script by Damond Benningfield

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