Venus Stands High
The planet Venus is riding high -- the dazzling "evening star" stands farthest from the Sun over the next few nights. It's well up in the southwest at nightfall, and doesn't set until around 9 or 9:30. Venus is so bright that you won't have any trouble spotting it -- it far outshines everything else in the night sky except the Moon.
This point in Venus's trek across the sky is known as greatest elongation.
It happens because Venus is one of two "inferior" planets -- planets that orbit closer to the Sun than Earth does. The other is Mercury.
These planets never stray very far from the Sun as seen from Earth. They swing back and forth from one side of the Sun to the other -- from evening sky to morning sky. As a result, they're visible only for a little while after sunset or before sunrise.
Venus is farther out from the Sun, so it can move farther from the Sun in our sky. At most, though, it's only about 45 degrees away -- just one-eighth of the way around the sky.
The other planets are "superior" planets -- they're outside our own orbit. They can move all the way around the sky with respect to the Sun. At their greatest elongation, they're directly opposite the Sun, so they rise at sunset and stand high in the sky at local midnight.
You'll never see Venus at midnight from the Lower 48 states. But you can see it this month, putting in a beautiful showing as it slides down the western sky in the early evening hours.
Script by Damond Benningfield, Copyright 2008
For more skywatching tips, astronomy news, and much more, read StarDate magazine.