A quasar is a celestial object that emits enough radiation to glow brighter than a galaxy.
类星体是一种天体,它辐射出的光比星系还要亮。
The energy that a quasar emits comes from a supermassive black hole at its centre.
类星体发射的能量来自位于其中心的超大质量黑洞。
When scientists first observed quasars in 1961, they thought they were stars, or star-like objects.
当科学家在1961年首次观测到类星体时,他们以为类星体是恒星或类恒星天体。
The name “quasar” is an abbreviation for “quasi-stellar radio source”, because the first observed quasars looked like stars that emitted lots of radio waves.
“类星体”这个名字是“类星射电源”的缩写,因为第一批观测到的类星体看起来像发射大量无线电波的恒星。
Scientists now know that quasars are the nuclei of young galaxies.
现在,科学家们知道类星体是早期星系的核心。
Even though quasars are very bright, most of them are billions of light years away, which means that observing them can provide information about the state of the universe in the distant past.
尽管类星体非常明亮,但大多数都在数十亿光年之外。这意味着,通过观察类星体,我们可以了解过去的宇宙。
The oldest discovered quasar formed nearly 13 billion years ago, at the very beginning of the universe’s life.
迄今发现的最古老的类星体形成于近130亿年前,那时候,宇宙刚刚形成。