Seyfert galaxies are energetic because they have a central black hole surrounded by a ring of gas.
赛非星系能量巨大，因为在其中心有-一黑洞，黑洞周围则环绕着环状星云。
2
In this paper, the distribution of four subclasses of four subclasses of Seyfert Galaxy Seyfert 1s, Seyfert 1.
文章比较了四种赛弗特星系子类1型赛弗特星系，1。
3
At the center of the starburst rings is the Seyfert nucleus, the believed signature of a supermassive black hole that is accreting surrounding gas and dust.