So when a quasar goes dormant, what's left are the things we associate with a normal galaxy — stars and gas swirling around a central and hidden pit of matter.

因此当一个类星体趋于休眠，留下来的就是我们通常和一个正常的星系联系起来的东西——星星和气体，他们围绕着一个隐藏着物质的大洞形成一个漩涡。

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These winds are generated in a swirling mass of matter around the equatorial region of a black hole, the accretion disk.

CNN: Black holes in a new light