Space Science

4. The average distance between Earth and the Sun (approx. 93 million miles).
6. A celestial object consisting of a nucleus of ice and dust that leaves a "tail" when near the sun.
7. A system of millions or billions of stars, together with gas and dust, held together by gravitational attraction.
8. An event in which the shadow of one celestial body falls on another.
9. Tilt The angle between an object's rotational axis and its orbital axis (causes seasons on Earth).
11. The regular, periodic rise and fall of the ocean's surface, typically occurring twice a day
12. A region of space having a gravitational field so intense that no matter or radiation can escape.
13. One complete orbit of a planet around the sun (defines a "year").
14. The curved path of a celestial object around a star, planet, or moon.

1. The spinning of a planet on its axis (defines a "day").
2. The region of interplanetary space between Mars and Jupiter where most asteroids are found.
3. The cloud of gas and dust from which our solar system formed.
5. The shape of the directly sunlit portion of the Moon as viewed from Earth.
10. The distance light travels in one year (approx. 9.46 trillion km).
12. The leading explanation for how the universe began.