Grade 8
Earth in the Solar System (Earth Sciences)
The structure and composition of the universe can be learned from studying stars
and galaxies and their evolution. As a basis for understanding this concept:
  • Students know galaxies are clusters of billions of stars and may have different shapes.
  • Students know that the Sun is one of many stars in the Milky Way galaxy and that stars may differ in size, temperature, and color.
  • Students know how to use astronomical units and light years as measures of distances between the Sun, stars, and Earth.
  • Students know that stars are the source of light for all bright objects in outer space and that the Moon and planets shine by reflected sunlight, not by their own light.
  • Students know the appearance, general composition, relative position and size, and motion of objects in the solar system, including planets, planetary satellites, comets, and asteroids.

Grades 9-12 (Earth Science)

Earth’s Place in the Universe
Astronomy and planetary exploration reveal the solar system’s structure, scale, and change over time. As a basis for understanding this concept:
  • Students know how the differences and similarities among the sun, the terrestrial planets, and the gas planets may have been established during the formation of the solar system.
  • Students know the evidence from Earth and moon rocks indicates that the solar system was formed from a nebular cloud of dust and gas approximately 4.6 billion years ago.
  • Students know the evidence from geological studies of Earth and other planets suggest that the early Earth was very different from Earth today.
  • Students know the evidence indicating that the planets are much closer to Earth than the stars are.
  • Students know the Sun is a typical star and is powered by nuclear reactions, primarily the fusion of hydrogen to form helium.
  • Students know the evidence for the dramatic effects that asteroid impacts have had in shaping the surface of planets and their moons and in mass extinctions of life on Earth.
  • Students know the evidence for the existence of planets orbiting other stars.
Earth-based and space-based astronomy reveal the structure, scale, and changes in stars, galaxies, and the universe over time. As a basis for understanding this concept:
  • Students know the solar system is located in an outer edge of the disc-shaped Milky Way galaxy, which spans 100,000 light years.
  • Students know galaxies are made of billions of stars and comprise most of the visible mass of the universe.
  • Students know the evidence indicating that all elements with an atomic number greater than that of lithium have been formed by nuclear fusion in stars.
  • Students know that stars differ in their life cycles and that visual, radio, and X-ray telescopes may be used to collect data that reveal those differences.
  • Students know accelerators boost subatomic particles to energy levels that simulate conditions in the stars and in the early history of the universe before stars formed.
  • Students know the evidence indicating that the color, brightness, and evolution of a star are determined by a balance between gravitational collapse and nuclear fusion.
  • Students know how the red-shift from distant galaxies and the cosmic background radiation provide evidence for the “big bang” model that suggests that the universe has been expanding for 10 to 20 billion years.
Energy in the Earth System
Energy enters the Earth system primarily as solar radiation and eventually escapes as heat. As a basis for understanding this concept:
  • Students know the relative amount of incoming solar energy compared with Earth’s internal energy and the energy used by society.
  • Students know the fate of incoming solar radiation in terms of reflection, absorption, and photosynthesis.
  • Students know the different atmospheric gases that absorb the Earth’s thermal radiation and the mechanism and significance of the greenhouse effect.
  • Students know the differing greenhouse conditions on Earth, Mars, and Venus; the origins of those conditions; and the climatic consequences of each.