首张黑洞视界尺度照片
影像来源与版权:Event Horizon Telescope Collaboration

说明:黑洞是什么样子的?为了找到答案,地球上的射电望远镜对黑洞进行了协调观测,这些黑洞是天空中已知的最大事件视界。单独来说,黑洞就是黑色的,但这些吸引力巨大的宇宙怪兽被炽热气体所包围。首张黑洞照片发布于昨天,它以低于所预期事件视界的尺度解析了位于M87星系中央的黑洞周围区域。如图所示,黑暗的中心区域不是事件视界,而是黑洞的阴影,那是中央区域气体发出的光被中央黑洞的引力作用吞噬了。阴影的大小和形状是由事件视界附近的明亮气体、强大的引力透镜偏转以及黑洞的自转来决定。事件视界望远镜(ETH)在解析这个黑洞阴影后,除了为爱因斯坦重力理论在极端区域下也能起作用给予了支持之外,还明确了M87的中央有一个质量约为60亿倍太阳的自转黑洞。EHT的任务还没有结束,未来的观测将朝着更高分辨率、更好跟踪变异性的方向发展,以及探索我们银河系中央黑洞附近的区域。
翻译:北京天文馆

First Horizon-Scale Image of a Black Hole
Image Credit & Copyright: Event Horizon Telescope Collaboration

Explanation: What does a black hole look like? To find out, radio telescopes from around the Earth coordinated observations of black holes with the largest known event horizons on the sky. Alone, black holes are just black, but these monster attractors are known to be surrounded by glowing gas. The first image was released yesterday and resolved the area around the black hole at the center of galaxy M87 on a scale below that expected for its event horizon. Pictured, the dark central region is not the event horizon, but rather the black hole’s shadow — the central region of emitting gas darkened by the central black hole’s gravity. The size and shape of the shadow is determined by bright gas near the event horizon, by strong gravitational lensing deflections, and by the black hole’s spin. In resolving this black hole’s shadow, the Event Horizon Telescope (EHT) bolstered evidence that Einstein’s gravity works even in extreme regions, and gave clear evidence that M87 has a central spinning black hole of about 6 billion solar masses. The EHT is not done — future observations will be geared toward even higher resolution, better tracking of variability, and exploring the immediate vicinity of the black hole in the center of our Milky Way Galaxy.
Astronomy Picture of the Day 04/11/2019