Heh. Yes, you've missed something quite important :)
There is one galaxy. It consists of many star systems, as I'm sure you've seen (press F6 for the galaxy map when you're in space).
You can't fly directly from one star system to another. That'd take zillions of years. Instead, you have to use one of the following methods:
Finite Probability Drive ("Fipro"): click the button on the left of your screen (in space, obviously). It brings up a list of popular worlds. Click one and you'll be taken there. They're in a few different star systems.
Infinite Improbability Drive ("Infimp"): you don't start with one of these, but you can buy them in most good space stations. When you've got one, you can click the button (also on the left) and type in the name of a world: again, you'll be taken there instantly.
Stardrive: this is the standard way to travel between star systems. Go to the galaxy map and zoom in (press F6 again). You'll see the star system you're currently in, and a circle around it that shows the range of your stardrive. If there's another star in range, click it to target it; then click the stardrive button from the main screen in space. You'll travel to that star.
A couple of things to note:
- you can buy different sized star drives. The bigger the drive, the further you'll be able to travel.
- stardrive is the only way to transport cargo from one system to another. You can't use Fipro or Infimp if you're carrying cargo
- stardrive travel uses Uridium fuel. You need enough fuel for the journey, or you won't be able to engage the stardrive. Obviously you need enough fuel for the return trip too if you want to come back (you can buy fuel at most spacestations, but the further out you go, the more likely it is that they'll be out of stock).
Finally, read
this to get a handle on the most common space stuff in the game.
Have fun :)
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