You take a cargo ship full of fuel, or a fuel depot, put it on that booster, get that in orbit, do a docking maneuver, refuel the spaceship, and head on to your destination, and this one is Mars.
Preuzimate teretnu letjelicu punu goriva ili spremište goriva, smještate ga na raketni pojačivač, pošaljete u orbitu, izvedete manevar sa spajanjem, napunite letjelicu gorivom i idete prema odredištu, u ovom slučaju, na Mars.