The equation in the Wiki entry implies that if a projectiles velocity is 0.99... of escape velocity, then it will fall back having reached a certain altitude. Let's say that altitude is in the region of L1. Let's put one of my theoretical Hammers directly underneath, then let's send a projectile up at a sliver under EV.
The flight path should be something like a very tall arc. The Moon is orbiting Earth so during the flight its position will change, and so will the location of L1. At the apex of its trajectory, the projectile will pass through the L1 region with diminishing vertical velocity but keeping it's horizontal (prograde) speed, so for a brief period it's moving parallel to the path of L1. At this point we intercept it with a net system. The problem, as far as I can tell so I'm happy to be corrected, is that there is going to be a speed differential, something like 150m/s if my simple sums are right.
As I write I am wondering if there is a solution where we can get an instantaneous relative velocity of zero, something like the inverse of a skyhook. If a projectile is angled to produce a retrograde flight path perhaps? This would almost certainly miss L1 proper I think. But maybe we can have a capture system that widely straddles the L1 region, extensions far apart to keep a stable network.
If we need a high speed capture system, we can refer to GK O'Neill/NASA studies of such things. As an alternative, I might propose a rotational system, with nets at the end of long rods. Linear velocity is translated into rotation and a braking system generates electricity from it.
Anyway, I'm out of my comfort zone now and I want to get on with writing about space stations made of iron.
EDIT:
I think the answer is L4 and L5?
The flight path should be something like a very tall arc. The Moon is orbiting Earth so during the flight its position will change, and so will the location of L1. At the apex of its trajectory, the projectile will pass through the L1 region with diminishing vertical velocity but keeping it's horizontal (prograde) speed, so for a brief period it's moving parallel to the path of L1. At this point we intercept it with a net system. The problem, as far as I can tell so I'm happy to be corrected, is that there is going to be a speed differential, something like 150m/s if my simple sums are right.
As I write I am wondering if there is a solution where we can get an instantaneous relative velocity of zero, something like the inverse of a skyhook. If a projectile is angled to produce a retrograde flight path perhaps? This would almost certainly miss L1 proper I think. But maybe we can have a capture system that widely straddles the L1 region, extensions far apart to keep a stable network.
If we need a high speed capture system, we can refer to GK O'Neill/NASA studies of such things. As an alternative, I might propose a rotational system, with nets at the end of long rods. Linear velocity is translated into rotation and a braking system generates electricity from it.
Anyway, I'm out of my comfort zone now and I want to get on with writing about space stations made of iron.
EDIT:
I think the answer is L4 and L5?
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