This is an older movie. I watched it sometime in my childhood so I'm guessing anywhere in between 1987 and 1995. I only remember a few details:
- The main characters are a boy and a girl
- The are guided somehow by an older man and this person is their only contact
- They travel in a ship called "The Tempest Fugit"
- I remember that they are somehow either lost or otherwise can't get back home. They may also just be stranded and not entirely in control of their ship.
The movie could be older than what I listed above. It may also be an animated series. I was quite young and can't remember many details.