Why do spacecrafts like the decommissioned Space Shuttles re-enter the atmosphere at such high speeds?

Question

I was just reading an article on the Space Shuttle Columbia tragedy and I began to wonder, why do they need to re-enter the atmosphere at roughly 17,000mph? Why not slow down to a less “burn up on re-entry” speed?

In: 2

Answer 1

Energy is king. It takes so much energy to change anything about an orbit. Creating an orbit is the most expensive part of space travel. That’s why they launch with giant fuel tanks and boosters nearly twice the size of the shuttle itself. But they detach during launch and they’re basically out of fuel by the time they get home.

You will find no better explanation not more entertaining than [this dry humor presentation ](https://youtu.be/Jb4prVsXkZU)