1. Royal Astronomical Society Oration H. S. Hudson & B. J. Welsch Space Sciences Lab, UC Berkeley

2. Solar lunch, Dec. 1, 2006 Abstract On longer time scales the linkage between body of the Sun and coronal structure is determined by vertical current systems, which maintain the stress in the force-free coronal volume. During times of flare or CME disruption of the coronal field, these current systems must evolve. We now have ample evidence for stepwise magnetic flux changes in flares; these can be detected by ground-based line-of-sight magnetographs. We discuss the nature of these changes, which correlate well with the impulsive-phase signatures in the lower solar atmosphere, including artifactual transients in the magnetograms and the launching of seismic waves into the solar interior. We discuss the physical nature of these sudden changes in the photospheric field and suggest that the Hinode observations will show them to preserve the vertical current.

3. Solar lunch, Dec. 1, 2006 A breakthrough: reliable observations of before/after fields (Sudol & Harvey 2005 case study) show permanent changes systematically for essentially all X-class flares

4. Solar lunch, Dec. 1, 2006 GONG SOHO/MDI B dB Flare of 2003 Oct. 29

5. Solar lunch, Dec. 1, 2006 Flare of 2001 Aug. 25 GONG + TRACE 1600A Other examples with GOES times

6. Solar lunch, Dec. 1, 2006 Note: The stepwise change in magnetic fields was first observed at BBSO by Wang et al. (see also Kosovichev-Zharkova, Solar Phys. 190, 459, 1999). Haimin is sure that the shear often increases in the before/after comparison (ApJ 649, 490, 2006).

7. Solar lunch, Dec. 1, 2006 Giovanelli (1948) Gold & Hoyle (1961) Longcope & Noonan (2000) Anzer & Pneuman (1982) A Cartoon Potpourri http://solarmuri.ssl.berkeley.edu/~hhudson/cartoons/

8. Solar lunch, Dec. 1, 2006 Choe & Cheng 2002 ApJL 574, 179 Therefore Aly was wrong…

9. Solar lunch, Dec. 1, 2006 Melrose 1997

10. Solar lunch, Dec. 1, 2006 What’s needed Hinode is here and SDO is coming. We need predictions from theories of magnetic restructuring FASR also can make precise before/after comparisons of the coronal field My preference is for a before/after magnetic constraint that reflects the persistence of vertical currents, but…