The concepts developed in this standard include the following:
- The Earth completes one revolution around the sun every 365 days. The moon revolves around the Earth about once every month.
-Due to the moon's revolution around the Earth, a lunar eclipse will occur when it moves into the Earth's shadow. A solar eclipse will occur when the moon moves between the sun and the Earth.
· Due to its axial tilt, the Earth experiences seasons during its revolution around the sun.
· The phases of the moon are caused by its position relative to the Earth and the sun. The phases of the moon include the new, waxing crescent, first quarter, waxing gibbous, full, waning gibbous, last quarter, and waning crescent.
· The sun is an average-sized yellow star, about 110 times the diameter of the Earth. The sun is approximately 4.6 billion years old.
· Our moon is a small rocky satellite, having about one-quarter the diameter of the Earth and one eightieth its mass. It has extremes of temperature, (virtually) no atmosphere, no water, and no life.
· The Earth is one of nine planets that revolve around the Sun and comprise the solar system. The Earth, third planet from the sun, is one of the four rocky inner planets. It is about 150 million kilometers from the sun.
· The Earth is a geologically active planet with a surface that is constantly changing. Unlike the other four inner planets, it has large amounts of life-supporting water and an oxygen-rich atmosphere. The Earth’s protective atmosphere blocks out most of the sun’s damaging rays.
· Our understanding of the solar system has changed from an Earth-centered model (Aristotle and Ptolemy) to the sun-centered model (Copernicus and Galileo).
· The NASA Apollo missions added a great deal to our understanding of the moon.
· Our understanding of the sun, moon, and the solar system continues to change with new scientific discoveries.

In order to meet this standard, the student will need to be able to:
· differentiate between rotation and revolution.
-distinguish between a solar and lunar eclipse and diagram how each occurs.
· describe how the Earth’s axial tilt causes the seasons.
· model the formation of the eight moon phases, sequence the phases in order, and describe how the phases occur.
· describe the major characteristics of the sun, including approximate size, color, age, and overall composition.
· create and describe a model of the Earth-moon-sun system with approximate scale distances and sizes.
· compare and contrast the Earth-centered to the sun-centered model of the solar system.
· analyze the differences in what Aristotle, Ptolemy, Copernicus, and Galileo observed and what influenced their conclusions.
· compare and contrast the surface conditions of the Earth, moon, and sun.· describe a contribution of the NASA Apollo missions to our understanding of the moon.