Will the moon be north, south, east or west?
Print Me Email to FriendTonight's Sky for Friday, Jul 11 2008
Tonight’s moon – in front of the constellation Libra – arcs across the south throughout the night. Andrew asked, What determines if the moon will appear in the northern, southern, eastern, western sky?
First of all, Andrew, as seen from the northern temperate latitudes, the moon never appears due north. Instead, the moon follows more or less the same path that the sun does each day. You know how the sun shines in your south windows, but not your north windows? Likewise, you’ll never be kept awake by a moon shining low in the due northern sky … unless you travel to the southern hemisphere!
Otherwise … the moon is generally eastward (east, southeast, northeast) soon after it rises (just as the sun is). The moon appears in the south when highest in the sky (also like the sun). And (like the sun) the moon sets generally westward (west, southwest, northwest).
So where you see the moon in the sky depends on how close it is to rising or setting. How can you know what time to expect moonrise or moonset? On average, as it pursues its monthly orbit around Earth, the moon rises 50 minutes later each day. I’m fond of this custom sunrise/sunset chart that also includes moon phases, and the rising and setting times of the moon.
