Buy the 2015 Old Farmer's Almanac!

The Near Side of the Moon

Credit: Photo NASA/JPL/Caltech
PrintPrintEmailEmail
Your rating: None Average: 3.8 of 5 (12 votes)

You've probably heard the expression, "The near side of the Moon." Read on to learn what this means.

The Near Side

The full Moon nearly always displays the same features to us.

This is essentially because the time it takes for the Moon to rotate once on its axis is identical to the time it takes for it to revolve once around the Earth.

If the Moon did not rotate, then we'd see one of its hemispheres when it was on one part of its orbit, and we'd see its opposite hemisphere when the Moon moved to the other side of its orbit.

Imagine a wary lion-tamer who keeps his face to the lion even as he steps all around the circular cage!

This is a special circumstance particular to the Moon, as we see both hemispheres of all the other bodies in the solar system as they rotate.

However, every moon in the solar system has this kind of captured rotation rate. It's caused by the strong gravity of its parent planet tugging and tugging on it for billions of years, slowing the spin, until it's captured and locked into the same period as its orbit.

Libration

Because of a phenomenon called libration, an apparent slight wobble resulting from the Moon's elliptical orbit, we can see about 59 percent of its surface over time.

What Lunar Features Can You See?

Most visible to the naked eye are the ancient lava flows that filled some of the Moon's older craters; they are enormous, smooth, dark, frozen seas, also known as maria. The lava came from the Moon's interior after large meteors hit and cracked its surface. Today, however, the Moon is cold and dead inside.

Related Articles

Full Moon Finder iPhone App

More Articles:

Comments

What date was this made on?

By Asia

What date was this made on?

i LOVE all the information I

By BONNIEBlU

i LOVE all the information I can receive on the moon phases etc

Amazing! Farmers almanac has

By harvesterloriann

Amazing! Farmers almanac has given me information I am looking for! For my own personal reasons, thank you!

Post new comment

Before posting, please review all comments. Due to the volume of questions, Almanac editors can respond only occasionally, as time allows. We also welcome tips from our wonderful Almanac community!

The content of this field is kept private and will not be shown publicly.
By submitting this form, you accept the Mollom privacy policy.

2015 Garden Calendar2015 Weather Watcher's Calendar2015 Recipes Calendar2015 Engagement Calendar 2015 Everyday Calendar2015 Country CalendarNew Year Cross StitchLobster Rope Doormats