A Spiral Nebula as a Stellar System, Messier 31

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A Spiral Nebula as a Stellar System, Messier 31

• By Edwin Hubble

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Not So Easy Astronomy
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Cepheid Light Curves
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Period Luminosity Relationship
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Extra Galactic Cepheids
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Light Curves of Novae
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Nova and Cepheid Frequency Distribution
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Distribution of Novae
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Conclusions

• Hubble Found

• Today We Find

• Found distance of M31 to be 275 kpc
• Found the total mass to be 2.4108 solar masses

• Stanek and Garnavich 1998 found the distance to
  be 780kpc
• Wilkinson and Evans 2000 found the total mass to
  be 1.21012 solar masses