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1·For any object, there is a critical radius, called the Schwarzschild radius, at which its mass will form a black hole.

对于任何一个物体，都存在一个被称为史瓦西半径的临界半径，在这个半径以内的质量将形成一个黑洞。

2·The X-rays are sent off into space before the matter crosses the Schwarzschild radius and crashes into the singularity. Thus we can see this X-ray emission.

在物质穿过希瓦兹凯尔德半径，被压挤成单一体之前；x射线会进人太空，因而我们能够发现这种x射线辐射。