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outward from the sun. The moon and Jupiter are the first two celestial objects to pop out after sunset.
• Understanding first quarter moon
• The moon looks much larger than Jupiter from Earth but that's only because the moon is much closer to us than Jupiter is. The moon, our closest celestial neighbor, lies somewhat more than 400,000 kilometers (250,000 thousand miles) away tonight, but Jupiter now resides at 1,800 times the moon's distance. Believe it or not, the volume of Jupiter, the solar system's largest planet, exceeds that of Earth by some 1,300 times and the moon's volume by 65,000 times.
• There's another way to look at the distances to the moon and Jupiter. Both of these bodies shine by reflecting the light of the sun. Whereas the light reflected from the moon takes about 1.3 seconds to reach Earth tonight, the light reflected from Jupiter must travel for a good 40 minutes before hitting Earth. By the way, light travels at 300,000 kilometers (186,000 miles) per second.
• How far is a light-year?
• The moon and Jupiter will travel westward across the sky tonight for the same reason that the sun travels westward during the day. The Earth rotates eastward upon its axis, creating the illusion that the sun, moon and planets go westward while the Earth stays still.
• Jupiter shines in front of the constellation Taurus the Bull. Look closely and you may note Jupiter in between the star Aldebaran and the Pleiades star cluster. If you can't discern the Pleiades with the eyes alone, try binoculars.
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