Earth, Moon, and Sun
By: Jacob Weitman
Section One, Earth and Space
Earth moves through space in two major ways, rotation and revolution.
Rotation is the spinning of Earth upon the axis . The rotation causes day and night. Revolution is the movement of an object that moves around another. One completion of Earth's revolution around the Sun causes the "365 1/4 day year." The path that Earth follows in its revolution is an orbit. The earth orbits around the sun in it's revolution. This orbit is not completely circular. It is an ellipse.
Gravity and Motion
The moons orbits the sun, much like the earth orbits around the sun. What keeps these objects in space from flying away is a force called gravity. Gravity is a force that attracts other object toward each other. This force is measured in newtons, after Sir Isaac Newton. Every thing around you is forcing down on you so that you stay on the earth and not just float away. The greater the mass of an object, the greater the gravitational effect it will have on object around it.
Two factors keep the moon in orbit of the earth, one of these factors is inertia, that is the force of an object resisting a change. This keeps the moon from coming to close to the earth and keeping it in its correct route. The other factor is gravity. These factors work together to keep the earth in orbit of the sun and the moon in orbit of the earth.
Phases, Eclipses and Tides
The moons moves on its axis and around the earth. By changing the relative positions of the moon, that could cause different phases of the moon, eclipses and tides. One day of the moon is just a little shorter then 29 of our days. 29 is how many phases of the moon there are. The same side of the moon always is facing the earth. The moon gives off it's light by reflecting the sun's rays off of it's surface.
When the shadow of the moon and the earth fall ion each other, it causes an eclipse. A solar eclipse occurs when the moon blocks out the sun from view of the earth. A lunar eclipse happens at a full moon when the earth is directly between the moon and sun.
Tides occur when the moon's gravity pulls on the earth at certain points. There are two different tides that can occur, spring and neap tides. Spring tides occur when the sun's gravity and the moon's gravity pull on the water. The neap tide occurs when the sun's pull is at right angles to the moon's pull.
There are three features to the moons surface , maria, craters and highlands. Maria are rocks formed by lava. Craters are large round pits created by the impact of a meteoroid. Meteoroids are huge chunks of rock from space. Highlands are a form of mountains and hills.
There are many characteristics of the moon that we identify today. Two characteristics are size and density. The moon is 3,476 kilometers in diameter. Which is one-forth the diameter. The moon only one-eightieth of Earth's mass. Temperature is another characteristic of the moon. The temperate on the moon ranges form 130 Celsius to -180 Celsius.
The moon formed by a theory called the collision-ring theory. When the earth was young a planet, our solar system was full of huge rocks and some of these rocks crashed into the earth braking up into smaller pieces. All those piece were forced together by earths gravity.
Come see the sky light up with a meteoroids and dinner!