Across
- 3. What is another name for the first four planets; Mercury, Venus, Earth, and Mars.
- 6. what is the first stage that stars begin as a cloud of gas and dust.
- 7. What is another name for the last four planets; Jupiter, Saturn, Uranus, and Neptune.
- 8. Masses of water, methane, and ice.
- 9. Relatively small (sand-grain to boulder size) pieces of debris chipped off asteroids or comets.
Down
- 1. Groups of stars with names from antiquity.
- 2. What indicates a stars temperature.
- 4. Meteoroid that survives the trip through the atmosphere and reaches Earth's surface.
- 5. Small rocky bodies that orbit the Sun.
- 9. Meteoroid that strikes Earth's atmosphere that is often called a "falling star.”