Congratulations. Your ship is now infested with an alien varmint called a ribblez. You can find these critters in your ships hold, misc tab.
Ribblez are pinkish-purple, kinda fluffy, and a solitary Ribblez makes a nice pet.
However, Ribblez breed. Quickly. If you let too many Ribblez breed in your hold, you will have a "Ribblez Gone Wild" event, which causes nasty things to your ship and hold. You can unload your Ribblez at a certain chain of stores. Farming Ribblez is a decent and easy way to get some spare change, as long as you are a careful and responsible breeder.