This document discusses how stars are classified based on their color, size, chemical composition, brightness, and location in the Hertzsprung-Russell diagram. It also describes the life cycles of stars from their birth as nebulae or protostars through their main sequence lifetimes fueled by nuclear fusion, to their deaths as red giants, planetary nebulae, white dwarfs, neutron stars, pulsars, or black holes depending on their original size.

1. Stars6th Grade Science

2. Classifying StarsColor Red Star = 3,200 °CYellow Star = 5,800 °CBlue Star = 20,000 °CSizeTiny = Neutron Star (Size of city)Small = Dwarf Star (Size of Earth)Medium = Size of our sun (100 Earths)Large = Giant Star (100 times bigger than our sun)Massive = Supergiants Star (400 times a giant star)

3. Classifying StarsChemicalsAmounts¾ Hydrogen¼ HeliumSmall amounts of other gases(Each star has different amounts of these)SpectrographSpread out light to see all of colorsChemicals absorb some light (appear black bands)

5. Classifying StarsBrightnessApparent BrightnessHow bright is the star in our sky at nightAbsolute BrightnessHow bright would it be if placed next to our sun

6. Measuring DistancesLight YearDistance light can travel in one year300,000 Km/Sec9,500,000,000,000 km

7. Measuring DistancesParallaxApparent change in position when you look at from different places

8. Hertzsprung-Russell Diagram (H-R)Measures color and absolute brightnessMain Sequence (90% of all stars)

9. Hertzsprung-Russell Diagram (H-R)

10. Hertzsprung-Russell Diagram (H-R)Betelgeuse = Red SupergiantRigel = Blue Supergiant

11. Lives of StarsNot really ALIVE – just used as an analogyBirthNebula (Large cloud of gas)Protostar (large collection of gas)Fusion PoweredHydrogen smashed to Helium

12. Lives of StarsLength of lifetime.Small Stars burn slowly200 billion years (200,000,000,000)Medium Stars burn medium (like our sun)10 billion years (10,000,000,000)Large Stars burn fast10 million years (10,000,000)

13. Lives of StarsDeathLow and Medium size starsRED GIANT (Huge star) as fuel runs outPLANETARY NEBULA - Throws away out layersWHITE DWARF - Remaining hot glowing centerBLACK DWARF – Glow is gone

14. Lives of StarsDeathLarge size stars (twice size of sun)SUPERGIANT (Enormous star) as fuel runs outSUPERNOVA- Explosive release of out layersNEUTRON STAR- Remaining hot glowing centerPULSAR – Spinning in space (100 times per second

15. Lives of StarsDeathMassive size stars (40 times bigger than sun)SUPERGIANT (Enormous star) as fuel runs outSUPERNOVA- Explosive release of out layersBLACK HOLE – Star is gone leaving only gravity behind