Active galactic nuclei (AGN) are among the most energetic phenomena observed in the universe. These luminous objects, powered ...

Optical and Spitzer IR light curves of the Seyfert galaxy NGC6418. A strong flare was observed in this object, which was accompanied by a dramatic increase in the strengths of the broad emission lines ...

Seyfert Galaxies They superficially resemble normal spiral galaxies, but something violent is going on in their central regions. They seem to have much in common with the most powerful radio ...

NGC 5643 is classified as a Seyfert galaxy because it hosts a supermassive black hole at its center. NGC 5643 is a giant spiral galaxy located about 55 million light-years (a light-year is the ...

NGC 4151 in Canes Venatici is a bright Seyfert galaxy with an active central black hole. It is class SAab. This galaxy has a ...

Around 118 million light-years away in the constellation of Leo Minor, it’s classed as a Seyfert galaxy because it has an active galactic nucleus—including a supermassive black hole—that ...

A cataclysmic energy flare ripped through our galaxy, the Milky Way, about 3.5 million years ago, a team of astronomers say. The so-called Seyfert flare started near the supermassive black hole in ...

115, No. 807, May 2003 Ultraviolet and Optical Properties of Na... ABSTRACT Narrow‐line Seyfert 1 galaxies (NLS1s) are remarkable for their extreme continuum and emission‐line properties, which are ...