[World Building] A Future History of Space Force

[Rupert]

Originally Posted by Verjigorm

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This is going to heavily influence the cost of the missile. Let's just use spaceships design as a rough benchmarking system: a missile with 18 fuel tank systems, 1 engine and 1 command center can have up to 6.75 mps of delta-v. This is enough to reach LEO and have a substantial amount of maneuver left over, but it can't reach higher or more distant orbits. A missile in LEO could target launch to *mars*(whether it is gonna survive the 9 month trip and be effective is a different story), as well as being able to intercept pretty much any target in cislunar space. To be able to target higher orbits, an earth based system would need to use staging, which increases the mass(and cost) of the missile substantially.

But you had to lift that orbiter into orbit, meaning an extra stage or two to launch it. If you can do that to an orbiter, you can loft a simple missile with the same system. The advantage a satellite has is that it can loiter until needed, possibly camouflaged as some civilian system (as many old Soviet satellites did) until it's needed. The disadvantages of this are a smaller payload (in this case mostly meaning less delta-V), and that it can be killed while dormant if the enemy identifies it.