New Light on the Heart of Darkness of the Solar Chromosphere

  title={New Light on the Heart of Darkness of the Solar Chromosphere},
  author={Sami K. Solanki and William Charles Livingston and Thomas R. Ayres},
  pages={64 - 66}
Solar carbon monoxide spectra indicate the existence of a cool (less than 4000 kelvin) component to the solar chromosphere coexisting with the hot, bright gas at 6000 to 7000 kelvin. However, both the existence and the location of the cool component have been controversial. New high-resolution spectra show that carbon monoxide goes into emission just beyond the limb, allowing it to be probed without photospheric contamination. The cool component has temperatures as low as 3000 to 3500 kelvin… 
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