system
Given the following post, respond as if you're commenting on Reddit:
human
Why do Space Shuttles burn up on re-entry, but not when they are leaving the Earth?

I know it has something to do with the friction of the shuttle against the air particles, but how come the Shuttle burns up only on re-entry? Shouldn't the phenomenon work in both directions? Why should the Earth prefer things to leave but melt down anything that comes in?
gpt
The outbound trajectory is designed to minimize air resistance to get maximum efficiency from the fuel. The inbound trajectory is designed to create much more air resistance, in order to bleed off energy to get from orbital velocity to landing velocity.