Whenever I hear this point made I think of the movie Master and Commander.

In the 1800s, being on a European wooden sailing vessel in the Pacific was, relatively speaking, very similar to being on another planet: - Takes months or years to get there: check - Fire could kill everyone on your vessel: check - "Nature" could kill you in innumerable ways: check - Some life sustaining and necessary items could be found along the way but many had to be brought with you: check