Light Years

Light Years=distance = the speed of light=300,000 km/s=the further you look into the distance, the further back in time you are looking= how far light travels in one year

1Life Cycle of a StarStars appear to be different because of Mass how big it is2. Stage of their life cycle where it is in its lifeLuminosity how it shinesSurface temperature how hot its surface is

2Mass measured on a balance -how much stuff is there not how much it weighs. Gravity causes weight

3Stages of stars are mapped out based on if they are a High mass or Low mass star Low Mass StarStage 1 nebula = cloud made out of star forming materials like dust and gas (gravity begins to contract the material)Stage 2 Protostar large mass of Hydrogen, high temp and contraction continues (not quite a star)(high temp causes contraction to stop and fusion to begin) (fusion is when two atoms are pushed together to form one)

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Stage 3 Star = undergoes fusion Hydrogen to Helium (orange, yellow, red) When Hydrogen is gone = gravity releases outer shell, star swells (the Hydrogen shell around the Helium core explains red swelling)Stage 4 Red Giant = shell shrinks and Helium fusion beginsStage 5 White Dwarf = small, hot, and dim

5High Mass StarStage 1 nebula = fusion much faster because a large mass burns faster (fusion of the Hydrogen to Helium eventually turns it to iron) Stage 2 Protostar = same as Low mass starStage 3 Red SuperGiant = similar to Low mass star

6Stage 4 -Super nova energy is released when the outer layer and elements are blown awayStage 5 -Newtron star ball of neutrons left behind or -Blackhole super dense remnants

7LuminosityTotal amount of power the Hydrogen radiates into spaceAmount of light that reaches usSun looks bright because it is so closeAs materials get hotter, they emit more light, so as they cool, they emit less light

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9Spectral ClassO blue/hotB blue-white/less hotA whiteF yellowish-whiteG yellowK orangeM red low energy/low temperature

10Hertzsprung-Russell DiagramImportant tool for how stars change over time

LuminositySpectral

temperature11Tools to study the UniverseTelescopes cause objects to appear largerOptical telescope uses visible light only

12Reflecting telescope

13Refracting telescope

14Radio telescopeCurved radio waves we cant see themFrequency too low for our vision to see

15ObservatoriesAudio light pollution

16SatellitesIn spaceDetect parts of electromagnetic spectrum(x-rays, gamma rays, radio waves)

17Space Shuttles and RocketsDansl'espace.wmvTo travel into space

18QuestionsWhat is the best piece of equipment that you could use to observe stars in space?

What does luminosity mean?

What diagram refers to colors and temperature when we observe stars?

What kind of telescope shows objects right-side-up?

Which stages of a stars life are represented in both large and small mass stars?

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