eARTH bASICS
The two main motions of the Earth are rotation and revolution. Rotation is the turning or spinning of a body on its axis while revolution is the motion of a body along a path around some point in space. The earth has another very slow motion called a precession which is a slight movement of the earth on its axis over 26,000 years.
RotationThe main results of the Earth's rotation are day and night. It's rotation equals about 24 hours.
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RevolutionThe Earth revolves around the sun in an elliptical orbit at approximately 107,000 kilometers per hour. At perihelion, the earth is at its closest to the sun. At aphelion, the earth is at its farthest.
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Earth Axis and SeasonsThe earth's axis of rotation is about 23.5 degrees. Because of this inclination of the earth's axis, the Earth has a yearly cycle of seasons relative to that point on the earth's distance to the sun.
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PrecessionThough the earth axis approximately maintains the same angle of tilt, the direction in which the axis points continually changes. The axis therefore traces a circle on the sky.
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Moon Basics
Lunar Surface
The moon has no atmosphere or water and therefore does not have the weathering or erosion as seen on the earth. But since it is not protected by an atmosphere, particles from space continually bombard the surface and smooth the landscape. As seen in the picture, craters, or round depressions, cover the moon's surface. Most are a result of rapidly moving debris. The moon also has highlands densely pitted light colored areas. Within these areas are mountain ranges with elevations up to 8 kilometers. The dark relatively smooth area on the moons surface is called a mare. Maria are ancient beds of basaltic lava from when asteroids punctured the lunar surface, letting magma bleed out. All lunar terrains are mantled with a layer of gray debris derived from a few billion years of bombardment from meteorites. This soil like layer is called the lunar regolith and is composed of rocks glass beads and fine lunar dust.
Eclpises
It is important to note that eclipses don't occur during every new or full moon phase. The moon's orbit must cross the plane of the elliptic for an eclipse to take place.