黑洞其实也是个星球,只不过它的密度极大, 靠近它的物体都被它的引力所约束(就好像人在地球上没有飞走一样)。对于地球来说,以第二宇宙速度来飞行就可以逃离地球,但是对于黑洞来说,它的第二宇宙速度之大,竟然超越了光速,所以连光都跑不出来,于是射进去的光没有反射回来,我们的眼睛就看不到任何东西,只是黑色一片。一些科学家认为光的速度比黑洞慢,所以被吸进去,当速度比黑洞快时就可以穿过黑洞边缘。Follow a basic explanation of what a black hole is an how it forms, this program explores what happen near and even inside a black hole based on current theories of gravitation. The great lengths scientists have to got to to test the theories are described.