What makes these floating parts of old satellites and spent rocket bodies so dangerous?

是什么让这些旧卫星的漂浮部件和用过的火箭体如此危险？

Yeah. Yep. The yellow are rocket bodies. Yep. And the red is debris. Yep. And then blue is unknown?

是的。是的。黄色的是火箭体。是的。红色是碎片。是的。然后蓝色是未知的？

After decades of launches since the dawn of the space age, Earth's orbit has become a junkyard of dead satellites and abandoned rocket bodies.

自太空时代开始以来，已经向地球轨道发射了几十次（航天器），这里现在已经变成了废弃卫星和火箭残骸的垃圾场。

On top of that, there are about 15,000 pieces of debris tracked today: dead satellites, dead rocket bodies and fragments of it.

最重要的是，今天追踪到了大约 15,000 块碎片：报废的卫星、报废的火箭体及其碎片。

They've built some technology that tracks everything in space, rocket bodies that have gone up there, satellites, all the debris from things that have collided and exploded.

他们已经建立了一些技术来跟踪太空中的一切，升空的火箭体， 卫星，以及碰撞和爆炸的物体的所有碎片。