Solar eclipses.
Abstract
The occasion of a total eclipse impacts the human observer with a bewildering rapid sequence of phenomena: mid-day cooling, failing light without accustomed color change, shadow-bands transiting the ground, cessation of bird sounds, possible frantic beating of jungle drums, Baily's beads, appearance of flame-like prominences, and most fantastic of all the solar corona. The author considers that although the corona is known to be 2 - 20(106)K, there is a lack of consensus on the heating mechanism, except the energy must be non-thermal and derived from surface and sub-surface convective motions. Theoreticians invoke the Joule dissipation of magnetic fields by Alfvén waves, electric currents in loop structures, or MHD turbulence. Although eclipse experiments to discriminate between these ideas generally fail, the sighting of 'plasmoids' was reported from the CFHT on Mauna Kea at the 1991 eclipse. Future experiments include: IR mapping of the coronal spectrum, spectroscopic velocity measurements, and the continued search for waves, nanoflares, and plasmoids.
- Publication:
-
International Conference on Plasma Physics ICPP 1994
- Pub Date:
- 1995
- DOI:
- 10.1063/1.49043
- Bibcode:
- 1995AIPC..345...27L
- Keywords:
-
- Solar Corona: Solar Eclipses;
- Solar Corona: Heating;
- 95.10.Gi;
- 96.60.Pb;
- 96.60.Rd;
- 52.35.Ra;
- Eclipses transits and occultations;
- Plasma turbulence