RAPID SUNSPOT MOTION DURING A MAJOR SOLAR-FLARE

A major solar flare on 15 November, 1991 produced a striking perturbat ion in the position and shape of the sunspot related most closely to t he flare. We have studied these perturbations by use of the aspect-sen sor images from the Soft X-ray Telescope on board YOHKOH, and with gro und-based data from the Mees Solar Observatory. The perturbation occur red during the impulsive phase of the flare, with a total displacement on the order of 1 arc sec. The apparent velocity of approximately 2 k m s-1 exceeds that typically reported for sunspot proper motions even in flare events. We estimate that the magnetic energy involved in disp lacing the sunspot amounted to less than 4 x 10(30) ergs, comparable t o the radiant energy from the perturbed region. Examination of the Mee s Observatory data shows that the spot continued moving at lower speed for a half-hour after the impulsive phase. The spot perturbation appe ars to have been a result of the coronal restructuring and flare energ y release, rather than its cause.