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Short Moon

June 19, 2016

The Moon makes itself scarce tonight. It’ll be “full” early tomorrow, so it rises shortly before sunset and remains in view for the rest of the night. But since the night is short, so is the time for moonwatching.

The length of time that the full Moon is in view varies by season and by latitude. At the equator, the full Moon is always in view for about 12 hours. As you move away from the equator, though, there’s a bigger difference based on the time of year.

That’s because Earth is tilted on its axis. At this time of year — summer starts tomorrow here in the northern hemisphere — the north pole dips sunward. So during the day, the Sun sails high overhead for northern latitudes, and it stays in view for a long time — up to about 16 hours as seen from the Lower 48 States, and up to 20 hours or more from parts of Alaska.

But since it lines up exactly opposite the Sun in the sky, the full Moon always does just the opposite of what the Sun does. So if the Sun is high in the sky and in view for a long time, then the Moon is low in the sky and in view for a much briefer time. Denver, for example, will see only about 10 hours of moonlight tonight, while Moon-deprived Anchorage will be graced with the Moon’s presence for only about seven hours. And tomorrow night will be about the same.

So wherever you are, enjoy the last evening of spring and the beautiful moonlight — but do it in a hurry.

More about the change in seasons tomorrow.

Script by Damond Benningfield

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