ar X iv : a st ro - p h / 99 05 14 7 v 1 1 2 M ay 1 99 9 Seyfert 1 mutation of the classical Seyfert 2 nucleus NGC 7582 1

We report the transition towards a type 1 Seyfert experienced by the classical type 2 Seyfert nucleus in NGC 7582. The transition, found at most 20 days from its maximum peak, presents a unique opportunity to study these rare events in detail. At maximum the Hα line width is of about 12000 km s. We examine three scenarios that could potentially explain the transition: capture of a star by a supermassive black hole, a reddening change in the surrounding torus, and the radiative onset of a type IIn supernova exploding in a compact nuclear/circumnuclear starburst. Subject headings: galaxies: active galaxies: individual: NGC 7582 galaxies: Seyfert – galaxies: starburst – supernova remnants