1. Stars Mr. Skirbst Physical Science Topic 25

2. Stars Composition: - determined by spectral analysis - hydrogen (60 – 80%) - helium (20 – 30%) - other (O, C, Ne, N)

3. Star size Supergiants * 1,000x size of the sun (ex. Rigel)

4. Star size Giants * 10 - 100x size of the sun (ex. Aldebaran)

5. Star size Medium (Main-Sequence) * same size of the sun (ex. Sun, Sirius)

6. Star size White Dwarfs * smaller than the Earth (ex. Van Maanens)

7. Star size Neutrons * only several kilometers in diameter * a teaspoon would have a mass greater than the entire Earth!

8. Relative Star Sizes Giant Star Neutron White dwarf Medium-sized Supergiant

9. Star temperature Color of star can help determine the surface temperature of stars COLORTEMP (oC) Blue35,000 White10,000 Yellow6,000 Red-Orange5,000 Red3,000

10. Star brightness Absolute brightness (magnitude) - light actually given off Apparent brightness (magnitude) - light observed by someone

11. H-R Diagram Hertzsprung-Russell Diagram * Relates absolute magnitude and surface temperature of stars H-R DiagramH-R Diagram H-R Diagram AnimationH-R Diagram Animation

12. Star Distances Parallax Method

13. Parallax