Moon, Venus, and Jupiter
The planets Venus and Jupiter blaze quite low in the dawn sky tomorrow like a pair of mismatched headlights. They're side by side, just a few degrees apart, and the crescent Moon is close by.
Venus and Jupiter are the brightest pinpoints of light in the night sky. But it's not hard to tell them apart, because Venus is a good bit brighter.
Both worlds vary in brightness as they and Earth orbit the Sun.
Right now, Venus is on the far side of its orbit as seen from Earth, which makes it a little fainter. But sunlight is illuminating most of the disk that faces our way, which makes the planet a little brighter. When you put them together, Venus is actually just about as faint as it gets.
Jupiter is on the far side of its orbit, too, but it's a lot farther away than Venus is. But Jupiter's a lot bigger, too. When you put those things together, Jupiter is also about as faint as it gets.
Even so, there's a noticeable difference between Jupiter and Venus. Venus is about six or seven times brighter than Jupiter. Since it's the planet on the left as they climb into view in the southeast around dawn, it looks like a celestial car is heading our way, with the left headlight decidedly brighter than the right.
Over the next few days, though, the two headlights will move apart, with Jupiter rising earlier and climbing higher by sunrise. But both will remain in good view until spring.
More about this lineup tomorrow.
Script by Damond Benningfield, Copyright 2007
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