Big Bang

2. the distance light travels in one year. It is a unit of distance, NOT A UNIT OF TIME. It is equal to 6 trillion miles.
5. leftover energy from the Big Bang.
6. the theory that the universe originated from a huge explosion from a point of singularity that released all matter and energy.
7. the change in light waves due to an object moving away from the observer. The farther away the star, the more red it appears. Proves that the universe is expanding.
10. a measurement of how much “stuff”, or the number of atoms, an object contains.
11. a measurement of how much space an object takes up.
12. a measurement of how much stuff is in a certain amount of space. Relationship between mass and volume.
14. the change in sound waves that occurs when the observer is moving away from or towards an object.
15. anything and everything that has a mass and takes up space.

1. a huge collection of stars, dust, and gas held together by gravity.
3. the force of attraction between objects. The greater the mass, the greater this force. The closer two objects are to each other, the greater this force.
4. the scientist who observed that the color of light from far away stars appear red, discovered the red shift of light, and used his data to support the idea that the universe is expanding. A telescope is named after him.
8. includes the Sun, planets, moons and other celestial bodies that travel around the Sun.
9. all of space and the energy in it. It includes galaxies and solar systems.
13. a ball of hot burning gas, made of primarily hydrogen and helium.