system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are humans more interested in planetary travel/discovery rather than fully exploring all of Earth first?
gpt
There is interest in exploring all the unknowns. There are teams studying the ocean floor and atmosphere and finding what they can on earth. 

But earth is still local and a limited space, and when considering the pace of humanity, space is where we will continue to expand. And like the many nomadic tribes before us, we always are looking out for the next possible place to settle.