Abstract

Magnetic fields play an important role in eruptive phenomena in the solar atmosphere. Observations show that magnetic shear, magnetic null point, magnetic connectivity and topology are all important for the occurrence of solar eruptions. In this paper, I discuss magnetic configurations that lead to eruptions on the Sun and the role of magnetic null points in triggering solar eruptions by case study of active regions 10486 and 10808. Studies show that not all flares require high shear, and magnetic complexity and emergence of twisted flux ropes are more important to produce eruptions. Magnetic null points favor flare production, but are not a necessary condition.