I mean fuel as the payload, to be used as fuel for future missions via something rendezvousing with it in orbit and picking up the fuel. You could think of it as one more stage, mathematically that's how you might treat it, but from an engineering perspective it's a qualitative difference versus what we have now.
Yes and no. They're lifting fuel into orbit, but all at once. That has three implications of needing more thrust for the engine than if we did it in multiple trips
That's true, but there is extra energy cost associate with putting it in orbit and then breaking orbit. Orbital calculations are about velocity, and delta-velocity, more than they are about height-above-ground.
Getting above the atmosphere is a big win, and may well make it worth it to do the final fueling from orbit. But in the end, getting to orbit may be as little as 100 miles of a multi-billion-mile trip.
jerf|3 years ago
kuu|3 years ago
jfengel|3 years ago
Getting above the atmosphere is a big win, and may well make it worth it to do the final fueling from orbit. But in the end, getting to orbit may be as little as 100 miles of a multi-billion-mile trip.