Evolution of a Star; Anatomy of the Sun

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Evolution of a Star Anatomy of the Sun

• Integrated Earth Systems
• 3

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Evolution Of A Star

• Nebula

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Evolution Of A Star

• Main Sequence
• Longest stage
• H to He (fusion)
• Star is breathing
• Rising energy (convection)
• Pulling gravity
• Maintains size

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Evolution Of A Star

• Giant and Supergiant
• 3rd stage
• Almost all H fused into He
• Core contracts
• Gaseous shell expands
• Cools
• Sun is only 5 done

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Evolution Of A Star

• White Dwarf
• End of fusion
• Loses outer gases
• Gravity core to collapse
• Hot, dense core of matter white dwarf
• Could cause explosion
• Nova

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Star Basics

• Brightness
• Depends on
• Temp, size, distance
• Learn by Light
• Only source of info
• Radiation/spectroscopy
• Missing light
• Absorbed by outer layers of the star
• Each element has its own pattern can be matched

• Color vs. Temp (554)
• Hot object through a prism
• Displays a spectrum
• Spectrum changes with temperature
• Hot short waves
• Cooler long waves
• Color we see wave length emitted
• Sun yellow
• Emits waves
• 600K

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Constellations

• Stars arranged into fixed patterns (apparent)
• 88 recognized constellations
• Northern and Southern Hemispheres
• Examples
• Ursa Major/Minor
• Draco
• Leo
• Orion (winter)

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Ursa Major/Ursa Minor
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Draco
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Leo
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Orion
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Scorpius
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