I'm trying to figure out how much force, over what period of time, is necessary to reach an earth-moon Lagrange point. L1 is about 323110 kilometers from earth, and an object there could remain (more or less) stationary relative to the earth and the moon. Earth gravity is working against the object the entire time it is traveling, until it gets to L1. And, of course, you don't want to have to apply a force the entire time the object is traveling. So, is the answer that the force needed is however much force you need to reach escape velocity? And then you would carry that speed until some other force slowed or stopped the object? What if you want to accelerate to a given speed such that by the time the ever-decreasing force of Earth's gravity brings the object to a stop you have reached L1? I may not know how to solve them, but I am sure there are equations answering these questions... Well, this is not a homework question. I am well out of college and didn't study math, so I am here because I don't have the basic understanding to do this myself. To the extent you can help me figure out what to do, how to do it, and what the answer is, I would appreciate it. Thanks. Edit: I didn't give you the payload mass. So I guess that's the other problem I have is that in order to solve this you need to know a lot about your rocket. But I guess to pick or design a rocket you'd have to know how much force you needed from your rocket to move the payload? So let's assume you're carrying a 10 kilogram object, just to make things easy.