Crossword Puzzle 2

4. a straight line across a circle through the center.
5. the path of a planet or an object that is moving around another thing in space.
8. the central part of an object.
9. a person who studies or knows a lot about the sun, moon planets and stars.
10. the outside part of something, the top of water.
11. inside toward or close to the center.
12. to travel around a new place to learn about it.

1. not like anyone or anything else.
2. all physical substances or a substance of a particular kind.
3. probe a spacecraft, without people that collects information and sends it back to Earth
4. how far it is from one place to another place.
5. on the outside; far from the center
6. the force that pulls everything toward the Earth.
7. objects, such a those in space or on Earth, moon, or planets are bodies in the space
8. large holes in the ground caused by something large hitting them.