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stellar spectra

stellar spectra

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pd

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• The Hertzsprung-Russel diagram

• a.k.a. HR diagram

• Vertical axis: L*

• Horiz. axis: Ts*

color of the star

• The Hertzsprung-Russel diagram

• a.k.a. HR diagram

• Vertical axis: L*

• Horiz. axis: Ts*

color of the star

• The Hertzsprung-Russel diagram

• a.k.a. HR diagram

• Vertical axis: L*

• Horiz. axis: Ts*

• Red giants – top right

• L* very big

– He burns hot and fast

• Ts* is low

– surface far from core

planetary nebula with white dwarf

Hubble image of Crab nebula

Chandra X-ray image of Crab nebula