The Observation of Possible Reconnection Events in the Boundary Changes of Solar Coronal Holes

  1. C. T. Russell,
  2. E. R. Priest and
  3. L. C. Lee
  1. S. W. Kahler1 and
  2. J. D. Moses2

Published Online: 21 MAR 2013

DOI: 10.1029/GM058p0229

Physics of Magnetic Flux Ropes

Physics of Magnetic Flux Ropes

How to Cite

Kahler, S. W. and Moses, J. D. (1990) The Observation of Possible Reconnection Events in the Boundary Changes of Solar Coronal Holes, in Physics of Magnetic Flux Ropes (eds C. T. Russell, E. R. Priest and L. C. Lee), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM058p0229

Author Information

  1. 1

    Physics Research Division, Emmanuel College, 400 the Fenway, Boston, MA 02115

  2. 2

    American Science and Engineering, Inc., Ft. Washington, Cambridge, MA 02139

Publication History

  1. Published Online: 21 MAR 2013
  2. Published Print: 1 JAN 1990

ISBN Information

Print ISBN: 9780875900261

Online ISBN: 9781118663868



  • Solar photosphere;
  • Magnetic flux;
  • Astrophysics


Coronal holes are large scale regions of magnetically open fields which are easily observed in solar soft X-ray images. The boundaries of coronal holes are separatrices between large-scale regions of open and closed magnetic fields where one might expect to observe evidence of solar magnetic reconnection. Previous studies by Nolte and colleagues using Skylab X-ray images established that large scale (≥ 9 × 104 km) changes in coronal hole boundaries were due to coronal processes, i.e., magnetic reconnection, rather than to photospheric motions. Those studies were limited to time scales of about one day, and no conclusion could be drawn about the size and time scales of the reconnection process at hole boundaries.

We have used sequences of appropriate Skylab X-ray images with a time resolution of about 90 min during times of the central meridian passages of the coronal hole labelled “Coronal Hole 1” to search for hole boundary changes which can yield the spatial and temporal scales of coronal magnetic reconnection. We find that 29 of 32 observed boundary changes could be associated with bright points. The appearance of the bright point may be the signature of reconnection between small-scale and large-scale magnetic fields. The observed boundary changes contributed to the quasi-rigid rotation of Coronal Hole 1.