IDENTIFY AND COMPARE THE COMPONENTS OF THE SOLAR SYSTEM AND EXPLAIN HOW THE POSITION OF THE SUN AND MOON AFFECT EVENTS ON EARTH.

A STUDENT SHOULD KNOW THAT:

A. PHASES OF THE MOON, ECLIPSES AND TIDES ARE CAUSED BY THE RELATIVE POSITION OF
     THE EARTH, SUN, AND MOON.

1. The moon revolves around the earth.  Because the moon rotates at the same rate it revolves, the same side of the moon is always facing earth.
   1. One half of the moon is always lighted by the sun as it revolves around the earth. The portion of the lighted side seen from the earth determines the phase of the moon. An eclipse occurs when the sun-moon-earth are in a line.
2. Tides are motions of oceans' water caused by the gravitational attraction between the earth, moon, and sun.
3. The highest tides occur when the sun-moon-earth are aligned.
4. Tides, phases of the moon, and eclipses occur regularly and predictably.

B. PLANETS OF VARYING SIZE, COMPOSITION, TEMPERATURE, GRAVITY, AND SURFACE
     FEATURES MOVE AROUND THE SUN IN ELLIPTICAL ORBITS.

1. Our sun is a star located near the center of our solar system.
2. Each of the other planets differs from the earth in terms of distance from the sun, atmosphere, gravity, surface features, temperature, heat energy, speed of rotation, length of year, and number of moons.
3. Comets travel around the sun in highly elliptical orbits. These comets produce a glowing head and a long tail.  The tail always points away from the sun.

TO UNDERSTAND THE CONCEPTS OUTLINED ABOVE, A STUDENT SHOULD BE ABLE TO:

• Interpret a diagram that shows how the positions of the earth, sun, and moon affect the tides, phases of the moon, and/or eclipses.
• Compare the physical characteristics of the components of the solar system, and compare the earth to other planets.