A rare galaxy type, polar ring galaxies have a substantial population of stars, gas, and dust orbiting in rings nearly perpendicular to the plane of the galactic disk.
极环星系是种稀有的星系类型，它们有着几乎和银盘平面垂直，呈环形公转的大量的恒星、气体和星尘。
2
The ring of stars saps the momentum of incoming gas, so it spirals in towards the black hole.
恒星环耗尽了引入气体的动量，所以气体就会向着黑洞盘旋地行进。
3
I put the kettle on the gasring and then went away and forgot about it.