| A | B |
|---|
| Hubble's Law | States that the farther away a galaxy is, the faster it is moving away from us |
| Big Bang | States that the universe formed in an instant, billions of years ago, in an enormous explosion. |
| Cosmic Background Radiation | Leftover thermal energy from the Big Bang. |
| Dark Matter | Matter that does NOT give off electromagnetic radiation. |
| Dark Energy | Mysterious energy that is causing the expansion of the universe to accelerate. |
| Age of Universe | 15 billion years |
| Age of Solar System | 5 billion years |
| Future of Universe | The universe will continue to expand until all the stars die out. |
| Gravity | Force that led to the formation of the solar system and the universe |
| Solar Nebula | A cloud of gas and dust that formed our sun and our solar system |
| Planetesimal | Small asteroid-like bodies that are the building blocks of the planets |
| Vera Rubin | Scientist who proved the existence of dark matter |
