P2: G

P2: G

1. An asteroid is a rock which orbits the Sun.

2. The moon is a natural satellite of Earth.

3. Comets are balls of ice and dust.

4. Comets have highly elliptical orbits and come from outside of Pluto's orbit.

5. Closet to a star a comet has a stronger gravitational pull, so it speeds up.

6. A NEO is a Near Earth Object (asteroid or comet) which may collide with Earth.

7. Telescopes and satellites are used to help monitor NEO's.

8. If a NEO is approaching towards we can launch a rocket containing explosives to break the NEO up.