| What is a black hole? Well, it's difficult to answer this question, since the terms we would normally use to describe a scientific phenomenon are inadequate here. 什么是黑洞呢？这个问题很难回答，因为我们通常用来描述一种科学现象的术语用在这里来解释是不够的。 Astronomers and scientists think that a black hole is a region of space (not a thing) into which matter has fallen and from which nothing can escape - not even light. 天文学家和科学家们认为黑洞是个空间区域，物体会掉进去，而没有物体能从中逃逸出来――即使是光也不能， So we can't see a black hole. A black hole exerts a strong gravitational pull and yet it has no matter. It is only space - or so we think. How can this happen? 所以我们看不到黑洞。黑洞产生很强的引力，而它却没有物质。它只是空间――或者我们认为是空间。这是怎样发生的呢？ The theory is that some stars explode when their density increases to a particular point; they collapse and sometimes a supernova occurs. 理论是一些星球的密度增长到特定的时刻就会爆炸。它们崩溃时会产生超新星。 From earth, a supernova looks like a very bright light in the sky which shines even in the daytime. 在地球上看去，超新星就像天空中非常耀眼的灯，即使在白天也能看到其闪光。 Supernovae were reported by astronomers in the seventeenth and eighteenth centuries. Some people think that the Star of Bethlehem could have been a supernova. 在17、18世纪，天文学家就有关于超新星的记录，一些人认为圣诞星可能是一颗超新星。 The collapse of a star may produce a White Dwarf or neutron star - a star, whose matter is so dense that it continually shrinks by the force of its own gravity. But if the star is very large (much bigger than our sun) this process of shrinking may be so intense that a black hole results. Imagine the earth reduced to the size of a marble, but still having the same mass and a stronger gravitational pull, and you have some idea of the force of a black hole. Any matter near the black hole is sucked in. It is impossible to say what happens inside a black hole. 一颗星崩溃可能产生吸引力，你就了解黑洞的力量。黑洞附近任何物质都会被吸进去，根本不可能说出黑洞里面发生了什么。 Scientists have called the boundary area around the hole the "event horizon." We know nothing about events which happen once objects pass this boundary. But in theory, matter must behave very differently inside the hole. 科学家们把这个洞的边缘区域称为"事界"。一旦物体经过这个边界，我们对所发生的事一无所知。但是在理论上，在黑洞里的物质的运动肯定与洞外有很大区别。 |
