We have studied the evolution of the photospheric magnetic Ðeld in active region NOAA 8668 for 3 days while the formation of a reverse S-shaped Ðlament proceeded. From a set of full-disk line-of-sight magnetograms taken by the Michelson Doppler Imager (MDI) on board the Solar and Heliospheric Observatory (SOHO), we have found a large canceling magnetic feature that was closely associated with the formation of the Ðlament. The positive Ñux of the magnetic feature was initially 1.5 ] 1021 Mx and exponentially decreased with an e-folding time of 28 hr throughout the period of observations. We also have determined the transverse velocities of the magnetic Ñux concentrations in the active region by applying local correlation tracking. As a result, a persistent pattern of shear motion was identiÐed in the neighborhood of the Ðlament. The shear motion had a speed of 0.2È0.5 km s~1 and fed negative magnetic helicity of [3 ] 1042 Mx2 into the coronal volume during an observing run of 50 hr at an average rate of [6 ] 1040 Mx2 hr~1. This rate is an order of magnitude higher than the rate of helicity change due to the solar di †erential rotation. The magnetic Ñux of the Ðeld lines created by magnetic reconnection and the magnetic helicity generated by the photospheric shear motion are much more than enough for the formation of the Ðlament. Based on this result, we conjecture that the Ðlament formation may be the visible manifestation of the creation of a much bigger magnetic structure that may consist of a Ñux rope and an overlying sheared arcade.

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We have made high-resolution observations of the Sun in which we identify individual sunquakes and see power from these seismic events being pumped into the resonant modes of vibration of the Sun. A typical event lasts about 5 minutes. We report the physical properties of the events and relate them to theories of the excitation of solar oscillations. We also discuss the local seismic potential of these events.