| A | B |
|---|
| Telescope | Instrument that gathers electromagnetic radiation (i.e. light) and focuses the light on an image |
| Refracting telescope | Bends light so as to focus the light at a point |
| Relecting telescope | Uses mirrors to bring light to the focal point. |
| Catadioptric telescope | A combination refraction-reflection telescope |
| Radio telescopes | Uses a 'dish' to gather electromagnetic radiation |
| Spectrum | An ordered array of frequencies in the electromagnetic spectrum |
| Infrared | Frequencies immediately below the visible frequencies |
| Ultraviolet | Frequencies immediately above the visible frequencies |
