Solar System

1. The four planets orbiting within 2 AU of the Sun
8. of icy bodies and a source of long-period comets.
9. The four planets orbiting beyond 2 AU of the Sun
12. The phase of the Moon when its sunlit side faces Earth.
14. The streak of light produced by a meteoroid burning in Earth’s atmosphere; a “shooting star.”
15. A body composed of ice and dust that orbits the Sun, usually in a very eccentric orbit, and that casts a lumi- nous tail produced by solar radiation pressure when close to the Sun.
16. The region beyond the Kuiper belt populated by
17. The phenomenon in which the shadow of Earth falls on the Moon, producing the relative darkness of the full Moon.

2. The average distance between Earth and the Sun;
3. The disk-shaped region of the sky beyond Neptune populated by many icy bod- ies and a source of short-period comets.
4. The plane of Earth’s orbit around the Sun. All major objects of the solar system orbit roughly within this same plane.
5. A region between the orbits of Mars and Jupiter that contains small, rocky, planet-like fragments that orbit the Sun.
6. The phenomenon in which the shadow of the Moon falls on Earth, producing a region of darkness in the daytime.
7. The major bodies orbiting the Sun that are massive enough for their gravity to make them spherical and small enough to avoid having nuclear fusion in their cores. They also have successfully cleared all debris from their orbital paths.
10. Temporary, relatively cool and dark regions on the Sun’s surface.
11. A relatively large icy body, such as Pluto, that originated within the Kuiper belt.
13. A meteoroid, or a part of a meteoroid, that has survived passage through Earth’s atmosphere to reach the ground.