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Getting Close

January 3, 2014

Earth is snuggling especially close to the two most dominant objects in the solar system right now — the Sun and the planet Jupiter. They’re on opposite sides of Earth, so Jupiter shines all night long.

Tomorrow, Earth will be closest to the Sun for the entire year — a point in our orbit known as perihelion. Our planet’s orbit is an ellipse, which looks like a slightly flattened circle. The average distance to the Sun is about 93 million miles. Right now, though, we’re about a million-and-a-half miles closer than that.

When Earth is closest to the Sun, it moves fastest in its orbit. Because of that, winter is the shortest season in the northern hemisphere — more than five days shorter than summer.

Earth is also overtaking Jupiter right now, so the planet will line up opposite the Sun on Sunday — a point known as opposition. Jupiter will rise at sunset and set at sunrise, so it’ll shine all night.

A planet is closest to Earth around the time of opposition, so it shines brightest. The combination of its closeness, its size, and the brightness of its clouds makes Jupiter especially eye-catching. It outshines everything else in the night sky except the Moon, which sets in early evening, and the planet Venus, which also disappears shortly after sunset right now.

Look for Jupiter low in the eastern sky as darkness falls, shining like a brilliant cream-colored star, and follow it as it arcs high across the south during the night.


Script by Damond Benningfield, Copyright 2013

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