click below
click below
Normal Size Small Size show me how
Chapter 8 Section 2
Vocabulary Chapter 8 Section 2
| Vocabulary | Definition |
|---|---|
| galaxy | a giant structure that contains dust, gases, and hundreds of billions of stars |
| universe | all of space and everything in it |
| light - year | the distance that light travels in one year |
| parallax | the apparent change in position of an object when seen from different places |
| giant star | a very large star, much larger than the sun |
| apparent magnitude | the brightness of a star as seen from Earth |
| absolute magnitude | the brightness of a star if it were a standard distance from Earth |
| Hertzsprung-Russell diagram | a graph relating the temperature and brightness of stars |
| main sequence | an area on the Hertzsprung-Russell diagram that runs from the upper left to the lower right and includes more than 90% of all stars |