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{{quote|«I have secured with a spectrograph attached to the 24-inch refractor spectrograms of this nebula which reveal a spectrum of more than common interest.»|style={{opencite}}}}
 
{{quote|«I have secured with a spectrograph attached to the 24-inch refractor spectrograms of this nebula which reveal a spectrum of more than common interest.»|style={{opencite}}}}
  
This is the paper where Slipher reports the observation of a continuous spectrum for a nebula (in the Pleiades). The finding is that the spectrum is that of the nebula itself and not an artifact from detecting something else. He attaches importance to the source, which is the nearby star (Merope) rather than to the physical reason for a continuous spectrum, which was a question ahead of his time or concern. He checked his assumption by contrasting with [[Sirius]]. The work was important as clarifying various types of nebulae.
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This is the paper where Slipher reports the observation of a continuous spectrum for a nebula (in the Pleiades). The finding is that the spectrum is that of the nebula itself and not an artifact from detecting something else. He checked his assumption by contrasting with [[Sirius]]. The work was important in clarifying that there exist various types of nebulae and pointing at interstellar dust for this one. He established indeed that the light reflects the light of the nearby Merope. The spectrum is completely continuous, but is ''not'' due to two-photon emission, in contrast to the spectra that Page{{cite|page36a}} would later find in emission nebula.
  
Excerpts of interest include, the motivation and reward for studying the spectrum:
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Excerpts of interest include the motivation and reward for studying the spectrum:
  
 
<center><wz tip="First observation of the 'faint' spectrum of a nebula in the Pleiades.">[[File:Screenshot_20240207_182250.png|400px]]</wz></center>
 
<center><wz tip="First observation of the 'faint' spectrum of a nebula in the Pleiades.">[[File:Screenshot_20240207_182250.png|400px]]</wz></center>
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<center><wz tip="Conclusions.">[[File:Screenshot_20240207_193756.png|400px]]</wz></center>
 
<center><wz tip="Conclusions.">[[File:Screenshot_20240207_193756.png|400px]]</wz></center>
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== References ==
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<references/>

Latest revision as of 14:35, 10 February 2024

On the spectrum of the nebula in the Pleiades. V. M. Slipher in Low. Obs. Bull. 2:26 (1912).  What the paper says?

Screenshot 20240207 180910.png


«I have secured with a spectrograph attached to the 24-inch refractor spectrograms of this nebula which reveal a spectrum of more than common interest.»

This is the paper where Slipher reports the observation of a continuous spectrum for a nebula (in the Pleiades). The finding is that the spectrum is that of the nebula itself and not an artifact from detecting something else. He checked his assumption by contrasting with Sirius. The work was important in clarifying that there exist various types of nebulae and pointing at interstellar dust for this one. He established indeed that the light reflects the light of the nearby Merope. The spectrum is completely continuous, but is not due to two-photon emission, in contrast to the spectra that Page[1] would later find in emission nebula.

Excerpts of interest include the motivation and reward for studying the spectrum:

Screenshot 20240207 182250.png

The description of the spectrum:

Screenshot 20240207 182425.png

The conclusions, that the nebula is dust that reflects light from the nearby star (here Merope):

Screenshot 20240207 193756.png

References

  1. The Continuous Spectra of Certain Planetary Nebulæ A Photometric Study. T. L. Page in Mon. Notices Royal Astron. Soc. 96:604 (1936).