for National Geographic News
The real showpiece, however, will be on the following night, when a thin crescent moon joins the planetary pair—creating a brief "unhappy face" in the sky.
The planets will appear closest together—an event known as a planetary conjunction—on November 30 around 4 p.m. Pacific time, and the moon will cozy up to the pair on the evening of December 1.
"This is set to be the best planetary gathering of the year, simply because it involves three of the brightest objects in the sky after the sun," said Geza Gyuk, director of astronomy at the Adler Planetarium in Chicago.
"As long as you have clear skies in the early part of the evening, this is one astronomical event that's hard to miss."
In fact, some historians think that a similar conjunction between Jupiter and Venus in 2 B.C. may be the source of the "star of Bethlehem" story related in the Bible.
The stellar pair would have appeared so close together, scholars think, that they might have seemed to meld into one brilliant beacon of light.
Blocked by a Thumb
Of the eight official planets in the solar system, five are visible at night without the aid of a telescope or binoculars.
Jupiter and Venus are particularly bright, partly because both have highly reflective clouds that completely envelop them, but also because Venus is Earth's closest neighbor while Jupiter is the largest planet in the solar system.
Both planets are currently easy to locate just after sunset in the southwestern sky.
During a conjunction, two or more of the naked-eye planets seem to be huddled close together—but this proximity is misleading.
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