Solar Physics

, Volume 84, Issue 1–2, pp 3–11 | Cite as

Naked sunspots

  • Margaret Liggett
  • Harold Zirin


Naked sunspots are spots seen in Hα to be devoid of associated plage. In magnetograms and K-line little if any opposite polarity field is found, and in soft X-ray images a blank appears in the region of the spot. In almost all cases studied in which naked spots resulted the spot groups had emerged in unipolar regions of the same polarity as the naked spot. At least half of the naked spots are associated with coronal holes. The naked spots are long-lived and show rotation rates close to the Newton-Nunn curve. Most of the naked spots had bright rims in Hα, and the one spot observed to disappear left no trace in the background magnetic field. These spots may be a means by which separation of p from f magnetic polarity occurs.


Magnetic Field Rotation Rate Opposite Polarity Coronal Hole Magnetic Polarity 
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Copyright information

© D. Reidel Publishing Co 1983

Authors and Affiliations

  • Margaret Liggett
    • 1
  • Harold Zirin
    • 1
  1. 1.Big Bear Solar Observatory, California Institute of TechnologyU.S.A.

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