How to Spot the Hiding Moon
The "disappeared" moon rises at 3 a.m. over a mountain lake in Colorado later this week.
Credit: Starry Night® Software

At this time of the month, some people are often puzzled by the disappearance of the moon.

Last night, there was a big bright full moon looming on the eastern horizon at sunset. But tonight it seems at first to be gone. Then, a little later in the evening, it rises in the east. Tomorrow night, it will put in an even later appearance.

So what?s happening with the moon?s game of astronomical hide-and-seek?

The moon is actually moving along in its orbit around the Earth. This has the effect of moonrise being approximately 50 minutes later each night.

By the weekend, the moon won?t be rising until about 3 a.m. ET in the morning.

The key to observing the moon if you don?t want to stay up all night is to look for it first thing in the morning.

The waning moon is best observed right after sunrise in the morning sky. Look in the southern sky (if you?re in the northern hemisphere) and there it will be, riding high in a clear blue sky (weather permitting).

Some people seem puzzled as to how the moon can be seen in daylight. The sun shines during the day and the moon shines at night, right?

Wrong. Nearly every day of the month, the moon spends about half the time in the daytime sky. The only exception is the one night in the month when the moon is full. That?s the only night when the moon is exactly opposite the sun in the sky [more moon images].

The rest of the month, the sun and moon share the sky at least part of the day. When the moon is new, it is so close to the sun that it can?t be seen at all, except when it gets too close, and actually eclipses the sun.

So, next week, have a look for the daytime moon any nice clear morning.

This article was provided to by Starry Night Education, the leader in space science curriculum solutions.