Comets have fascinating spectra. When they are in quiescence, far from the sun, the comets shine by reflected sunlight, and the spectra resemble that of solar type star (G2V), the sun! As the comets come into the inner solar system they become active and their spectra become dominated by emission lines from carbon compounds.

Some of the strong carbon features include (in Angstroms): 3880 CN (STRONG in comets), 4056 C3 complex (STRONG in comets), 4217 CN, 4380 C2 Swan, 4738 C2 Swan, 5165 C2 Swan (STRONG), 5635 C2 Swan, 6122 C2 Swan

  • The Latest Comet Ephemerides
  • Catalog of Cometary Emission Lines

    "Active" Comets

    Comet Tabur x

    "Quiescent" Comets

    Comet Lovas x