system
Given the following post, respond as if you're commenting on Reddit:
human
[Dune/Avatar] Question about the unobtainium/spice.

I just saw the movie Dune, have no read the books, and they explain within the first 10 minutes about how spice is nessecary for space travel.

Now this raises the obvious question; How did they get to a deserted desert planet in the first place to acquire the material nessecary for space travel? Was spice in small quantities in other worlds? Did they use other methods? I'm confused, it was never explained in the movie even though it's something I thought about immediately.

This also came up in the movie Avatar. They explain in the movie that unobtainium is used for interstellar travel. Again, what did humans do before they acquired this material? How did humans get to the planet in the first place? I haven't seen this movie in years though, so maybe I am missing something. Just a side-note on a related topic to Dune I guess.
gpt
In avatar, they just travelled there slower and less efficiently. Like how we had coal-powered vehicles before oil-powered. Simple enough.

In dune, spice is necessary for *safe* interstellar travel. So how did they get to Arrakis? With a *significant* death toll. Spice changed interstellar flight from something only reckless explorers would do to something you can base a civilization on.