嘘！听听黑洞的声音……

black hole Sagittarius A

Sagittarius A*, the black hole at the center of the milky way. EHT Collaboration

人马座A*，银河系中心的黑洞

北京时间5月12日21时07分，在全球同步召开的新闻发布会上，天文学家展示了位于银河系中心的一个超大质量黑洞的首张照片。这张照片由事件视界望远镜（EHT）合作组织通过分布在全球的射电望远镜组网“拍摄”而成。2019年4月10号，人类首次拍摄到了黑洞照片。三年后，这张宝贵的新照片揭开了更多等待我们去探索和发现的奥秘。

This black hole was named Sagittarius A*. It weighs seven-million-times as much as the Sun and is 27,000 lightyears away.

该黑洞被命名为人马座A*，质量是太阳的七百万倍，距离太阳2万7千光年。

For the first time, humanity has stared into the dark heart of unfathomable chaos at the center of the Milky Way and brought its shadowy form into focus. The object staring back at us, Sagittarius A*, is a monstrous black hole that binds our home galaxy together.

这是人类第一次凝视着银河系中心那深不可测的混沌黑暗，并将焦点对准了黑暗深处这个神秘莫测的形态。在我们身后望着我们的是人马座A*，一个巨大的黑洞，它将我们所生活着的星系都联系在一起。

左M87* 右Sgr A*

This is a sonification — translation into sound — of the latest image from the Event Horizon Telescope (EHT) of the supermassive black hole at the center of the Milky Way. Using a radar-like scan, the sonification begins at the 12 o’clock position and sweeps clockwise. The material that is closer to the black hole and hence moving faster corresponds to higher frequencies of sound. This sonification was processed in a special way to allow a listener to hear the data in 3D stereo sound.

这一段视频将事件视界望远镜（EHT）捕捉到的人马座A*的最新图像进行了超声化处理。即使用类似雷达的工具，自黑洞的12点钟方向进行顺时针扫描。视频中声音的高低变化代表了检测工具距离人马座A*黑洞的远近。物质越接近黑洞因而移动得更快，对应更高频率的声音。这种超声化处理用一种特殊的数据处理方式，以 3D 立体音的形式将黑洞的声音传递给听众。

The team observed Sagittarius A* on multiple nights, collecting data for many hours in a row, similar to using a long exposure time on a camera. Although we cannot see the black hole itself, because it is completely dark, glowing gas around it reveals a tell-tale signature: a dark central region (called a “shadow”) surrounded by a bright ring-like structure. The new view captures light bent by the powerful gravity of the black hole. The discovery also yields valuable clues about the workings of black holes, which are thought to reside at the center of most galaxies.

拍摄团队在多个夜晚观察了人马座A*，连续数小时收集数据，这一操作类似于在相机上使用长时间曝光。由于它是完全黑暗的，所以我们无法看到黑洞本身，但它周围的发光气体揭示了一个明显的特征：一个黑暗的中心区域（称为“阴影”），周围环绕着明亮的环状结构。新的照片捕获了被黑洞的强大引力所弯曲的光，同时还发现了“位于大多数星系中心”的黑洞是如何运作的宝贵线索。

The surprising thing about this image is that it looks so similar to the image of M87* we published three years ago. The reason for the similarity is that while the M87* black hole is about 1,000 times bigger, the Sagittarius black hole is about 100 times closer. Both of them obey Einstein’s theory of general relativity. To a physicist this is important. Relativity has been around for a century and it is still proving to be accurate. Even Einstein himself might have been surprised by that!

令人惊讶的是，这张图片看起来与我们三年前发布的M87 *的图像非常相似。虽然M87*黑洞比人马座黑洞大约1000倍，但人马座黑洞比它离我们近约100倍。它们都遵循爱因斯坦的广义相对论。这一点对于物理学家来说十分重要，因为相对论已经存在了一个世纪，如今仍然被证明是准确的。相信爱因斯坦本人也会对此感到惊讶！