The Moon is the only natural satellite of the Earth. While second only to the Sun as far as brightness in the sky, the Moon is king of the night sky. This title is somewhat deceptive. The Moon dominates the night sky but actual has no light source of its own. The reflective surface of the moon only redirects Sun light from the other side of the Earth.
Helping to illuminate the night sky is not the only role of the Moon. Even though it is thousands of miles away the Moon has important jobs in the sky and on Earth.
Surface of the Moon
Because of the rotation of the Moon in association with the Earth, there is a far and near side of the moon. The far side is typically not seen because the Moon presents the same face to the Earth each night. Small sections of the far side can be seen from Earth because of the elliptical orbit of the moon and its relation to the Earth throughout the year.
Layers of the Moon
The Moon has similar layers to the Earth although the components are different. Both heavenly bodies have a crust, mantle, and a core.
The Moon’s crust is thicker than the crust and the Earth. The Moon’s crust also has more damage from collisions throughout the ages. The Moon does not have the atmosphere of the Earth which helps to burn up many fragments in the sky. Because of this, impact is not stopped on the moon.
The mantle of the Moon is made up of magnesium and iron. While the mantle was forming, dense material would sink but lighter material would rise to upper layers.
The core of the Moon is only 250 miles wide and makes up about 1% of the total mass of the satellite.
Effects on Earth of the Moon
Even though there is little gravity on the Moon in comparison to Earth, there is still a strong bond between these two bodies. The most commonly know effect is the tide cycle on Earth. Depending on where the Moon is located, there is a stronger pull on the Earth and the oceans. It is this pull that creates the high tides daily.
Another effect is the rotation of the Earth. Because of the pull of the moon, the Earth is slowly decreasing its rotational speed. This happens over centuries but this does not change the fact that the Moon does play a part in this change. Just as the moon has stabilized to always show one face, the Earth could reach this point from the perspective of the Moon in the distance future.
The Moon is a fascinating heavenly body. It appears that it also continues to reveal new secrets with the discovery of water. This discovery could change the role of the moon and the direction for space travel in the near future.
Source:
Spudis, Paul D. “Moon.” World Book Online Reference Center. 2004. World Book, Inc. Retrieved November 13, 2009 from <http://www.worldbookonline.com/wb/Article?id=ar370060>.
 |
