偶看新闻友田彩也香步兵三部曲:探知黑洞
来源：百度文库 编辑：偶看新闻 时间：2024/04/27 06:58:44
Probing a Black Hole
by Bruce Dorminey 胡德良 译
How do you probe a supermassive black hole? Take a look at the pulsars that orbit it. These rapidly spinning neutron stars flash regular radio pulses, and in an upcoming issue of The Astrophysical Journal astronomers say that the timing of such pulses could provide a new understanding of the 4 million solar mass black hole at the center of the Milky Way. Scientists have speculated that physics as we know it could break down in the presence of such a strong gravitational force. If that's the case, any flashes from nearby pulsars would appear to speed up or slow down when viewed from Earth, with their clocklike arrival times running early or late and likely dependent on where their orbits were in relation to the black hole. In the process, the astronomers also hope to determine Sagittarius A*'s spin rate and true mass down to an accuracy of about 1 part in a million. First, though, they have to find pulsars close enough to this gravitational monstrosity to be useful. And that's not expected to happen until the Square Kilometer Array comes online early next decade. 如何来探知超级黑洞呢？看一看围绕黑洞旋转的脉冲星就知道了，这些快速旋转的中子星定期闪射出无线电脉冲。天文学家们在即将出版的一期《天体物理学杂志》上报道说，这种脉冲的发射时间可以让人们对银河系中心质量为400万个太阳的黑洞有一个新的认识。科学家们推测，我们所了解的物理规律在这么强大的引力作用下会遭到破坏。如果情况是这样的话，当我们在地球上观察的时候，附近脉冲星发出的任何闪光随着有规律的到达时间变得或早或晚，就会显得要么加速、要么减速，这很可能取决于脉冲星的轨道相对于黑洞的位置。在该过程中，天文学家们还希望确定人马座A的旋转速度和实际质量，将质量的测量精确到百万分之一。但是，他们首先需要找出距离这个引力巨大的庞然大物足够近的脉冲星，然而这一天只有在下一个十年初期“平方千米射电望远镜阵列”上线之后才会到来。
译自：美国《科学》杂志网站（20 December 2011, 5:07 PM）
原著：Bruce Dorminey