How will SpaceX make in-space refueling happen?
Like all infrastructure developments, they start small and expand as has be seen in recent years where EV charging infrastructure went from nothing to a vast network.
So to with SpaceX, they will build things step-by-step as more rockets are produced from the factory.
(Image: SpaceX)
Ship-to-Ship Transfer
The primary method currently in development involves direct ship-to-ship propellant transfer.
This is done by launching a tanker variant of Starship into orbit to meet with another Starship, where propellants are transferred directly from one ship to another.
The first test of this is planned for 2025, where two Starships will dock and transfer fuel in orbit. However this schedule may be changed to 2026.
The advantage of this method is that it is a simple adjustment to the current ship design, so can be implemented quickly. A disadvantage is that the amount of fuel transferred is limited.
The ship-to-ship transfer is seen as a stepping stone to establishing more permanent fuel depot solutions in orbit.
In-Space Fuel Depot
There are also plans for using a Starship as a fuel depot. This involves launching a Starship configured as a depot into orbit, where it would be filled by multiple tanker Starship flights.
This depot would then serve as a storage and refueling point for other Starships, particularly for missions requiring extensive refueling, like lunar or Mars missions.
The depot would not re-enter Earth's atmosphere and would remain in orbit to facilitate these operations.
One of the key advantages of the depot is that there can be a regular filling cycle independent of any particular mission.
Conclusion
Yes, in-space refueling is new and complicated. However, it opens up many opportunities for long-distance space travel with much greater payloads.
It will start small and expand over time to the point where fuel production will also be happening off-Earth. It is at this point the rapid expansion will begin.
Would Abraham Lincoln have applied these words to space now as he did to railroads then? "The railroad is the pioneer of progress; it stimulates the energies of the people, develops the resources of the country, and is the great instrument of civilization."