• The solar system consists of the sun, moon, Earth, other planets and their moons, meteors, asteroids, and comets. Each body has its own characteristics and features.
• The distance between planets and sizes of the planets vary greatly. The outer, ―gas planets are very large, and the four inner planets are comparatively small and rocky.
• Gravity is a force that keeps the planets in motion around the sun. Gravity acts everywhere in the universe.
• Planets revolve around the sun, and moons revolve around planets. A planet rotates upon an axis.
• A dwarf planet revolves around the sun, and can maintain a nearly round shape as planets do, but it cannot move other objects away from its orbital neighborhood.
• As Earth rotates, different sides of Earth face toward or away from the sun, thus causing day and night, respectively.
• The phases of the moon are caused by its position relative to Earth and the sun.
• Earth is a rocky planet, extensively covered with large oceans of liquid water and having frozen ice caps in its polar regions. Earth has a protective atmosphere consisting predominantly of nitrogen and oxygen and has a magnetic field. The atmosphere and the magnetic field help shield Earth’s surface from harmful solar radiation. Scientific evidence indicates that Earth is about 4.5 billion years old.
• Seasons are caused by a combination of the tilt of Earth on its axis, the curvature of Earth’s surface and, thus, the angle at which sunlight strikes the surface of Earth during its annual revolution around the sun.
• Tides are the result of the gravitational pull of the moon and sun on the surface waters of Earth.
• The ideas of Ptolemy, Aristotle, Copernicus, and Galileo contributed to the development of our understanding of the solar system.
• With the development of new technology over the last half-century, our knowledge of the solar system has increased substantially.
• describe the planets and their relative positions from the sun.
• compare the characteristics of Pluto to the planets and explain its designation as a dwarf planet.
• design and interpret a scale model of the solar system. (A scale model may be a physical representation of an object or concept. It can also be a mathematical representation that uses factors such as ratios, proportions, and percentages.)  explain the role of gravity in the solar system.
• compare and contrast revolution and rotation and apply these terms to the relative movements of planets and their moons.  model and describe how day and night and the phases of the moon occur.
• model and describe how Earth’s axial tilt and its annual orbit around the sun cause the seasons.
• describe the unique characteristics of planet Earth.
• discuss the relationship between the gravitational pull of the moon and the cycle of tides.
• compare and contrast the ideas of Ptolemy, Aristotle, Copernicus, and Galileo related to the solar system.
• create and interpret a timeline highlighting the advancements in solar system exploration over the past half century. This should include information on the first modern rockets, artificial satellites, orbital missions, missions to the moon, Mars robotic explorers, and exploration of the outer planets.