Universe Vocabulary

4. star: A very dense star made mostly of neutrons. It has very powerful gravitational force nearby because the whole mass of a star is pulled into one object just a few miles across.
6. An object that orbits another object.
7. A large body in outer space that circles around the sun or another star.
8. system: A set that includes a star and all of the matter that orbits it, including planets, moons, asteroids, comets, and other objects.
9. A way energy moves from one place to another.
12. Rocks floating around in space. Some are the size of a pick-up truck. Others are hundreds of miles across.
15. The streak of light caused when a meteoroid enters a planet’s atmosphere and starts to burn from the heat of friction.
16. The explosion of a star that makes it as bright as a whole galaxy.
17. A force that pulls matter together.
18. An icy rock that lets off gas and dust, which may form tails when it is flying close to a sun.
19. hole: A place in space where matter and light cannot escape if they fall in.
20. The star in the center of our solar system.

1. year: It’s not a year, or an amount of time at all. It’s the distance light travels in one year.
2. A natural object that travels around a bigger natural object.
3. The amount of matter something is made of.
5. All of space and time, and everything in it. It’s everything ever!
10. Spectrum: The name for all the different kinds of light and energy in the universe. This includes radio waves, microwaves, infrared radiation, visible light, ultraviolet light, X-rays, and gamma rays.
11. light: The part of the electromagnetic spectrum that we can see with our eyes. It’s all the colors of the rainbow.
13. A ball of shining gas, made mostly of hydrogen and helium, held together by its own gravity.
14. A cloud of dust or gas found between stars.
17. A collection of thousands to billions of stars held together by gravity. The galaxy we live in is called the Milky Way.