| A | B |
|---|
| meteoroid | small rock or dust in space |
| meteor | light streak see when meteoroid burns up as it enters Earth's atmosphere |
| meteorite | piece of meteoroid that falls to Earth |
| comet | made up of ice, rock & dust |
| geocentric | model that puts the Earth at the center of solar system |
| heliocentric | model that puts the Sun at the center of the solar system |
| ellipse | an oval shape (like a planet's orbit) |
| nuclear fusion | hydrogen atoms fuse together at center/core of sun producing lots of energy |
| solar wind | stream of electrically charged particles streaming out from the sun into space |
| northern lights | when electrically charged particles from the sun enters Earth's atmosphere and heat up gases in the atmosphere and they glow |
| terrestrial planet | planets with rocky surfaces |
| Gas giant planet | planets made up of mostly hydrogen & helium |
| asteroid | large rocks in space, most in asteroid belt between Mars & Jupiter |
