system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do NASA and other space agencies prevent all the satellites orbiting the earth from crashing into each other? How do we launch rockets without smashing into the satellites?
gpt
Here is a simplified explanation.

The space agencies (not just NASA) keep a very close watch on orbits.  The paths of each satellite are quite predictable and many of them can be steered to correct the orbit.  With a bit of planning, there are plenty of gaps.  Here's why.

What we call space starts about 100 miles up.  Most satellites are in a range of about 100 miles to 22,500 miles up.  To compare with something more familiar, aircraft usually have to be a minimum of 1000 feet apart in altitude.  Even a small range from 100 miles to 200 miles up gives over 500 layers 1000 feet apart.   

Now consider that the satellites could be anywhere over the earth's surface, which is roughly 200,000,000,000 square miles.  That's a lot of room.