system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How does Nasa know the exact course to chart with their space probes to get them on different planets?

ELI5: How does Nasa know the exact course to chart with their space probes to get them on different planets?
gpt
Well they're literally rocket scientists...

No, seriously, NASA has some of the finest astronomers in the world, who have learned how to perform the complex trajectory calculations necessary to fire a space probe travelling thousands of miles per hour, off of one planet travelling sixty-five thousand miles per hour, towards another planet travelling fifty-four thousand miles per hour (Mars, for the sake of argument).

To use a sports analogy, a hockey player doesn't pass the puck to where his teammate is, he passes it to the point his teammate will be by the time the puck arrives. NASA is doing pretty much the same thing, just on an exponentially larger scale and using rockets.