| A | B |
|---|
| galaxy | a giant structure that contains hundreds of billions of stars |
| apparent magnitude | the brightness of a star as seen from earth |
| spiral galaxy | a galaxy whose arms curve outward in a pinwill pattern |
| elliptical galaxy | a galaxy shaped like a flattened ball, containg only old stars |
| irregular galaxy | a galaxy that doesn't have a regular shape |
| spectroscope | an instrument used to view the different colors of light produced by different sources |
| telescope | a device built to study distant objects by making them appear closer |
| stars | a hot ball of glowing gas in space that appear as small points of light in the sky |
