Yeah I will make it possible to travel between planets, I might even put multiple Donut Worlds in the same Orbit as the starting World, so you dont even need to leave the Star System to get to a habitable World. But that is gonna be configurable.
As for Science, there could be multiple Systems to choose from, crafting the Recipe from Materials using Experiments and (optional) RNG to see if they succeeded. You could steal Science from NPCs, or buy it, or hire an NPC to do your Science, or Dungeon Loot, or maybe even Factorio Style. The options will be plenty and more than what I just said. ^^