Everything is on the small order of magnitude when compared with getting into Earth orbit. As the quote goes, "Once you get to earth orbit, you're halfway to anywhere in the solar system."
> As the quote goes, "Once you get to earth orbit, you're halfway to anywhere in the solar system."
In terms of delta-v, yes. Going to the moon only takes 50% more delta-v than going to LEO. But the rocket equation makes getting that extra 50% a lot harder. Time for more staging and complexity and still having terrible payload fraction.
That might be Heinlein's most annoying quote ever and boy does it have competition.
It is very expensive to change orbits. If you had two space stations like the ISS with ascending nodes 180 degrees from each other it would be about as expensive to transit between them as it is to launch a rocket from the Earth to begin with. See
You've got the advantage in space that you can use electric rockets with a high specific impulse. Back in the 1950s folks like von Braun imagined that manned space flight might use electric rockets but after they discovered the Van Allen belts they discovered this is much too slow to make it through the magnetosphere.
> If you had two space stations like the ISS with ascending nodes 180 degrees from each other it would be about as expensive to transit between them as it is to launch a rocket from the Earth to begin with.
1+1 = 2 2/2 = 1; technically halfway.
To interpret “halfway to anywhere” that way is missing the point. Going from LEO to LEO wasn’t the point of “halfway to anywhere”. Yes a bit exuberant but not far off.
