You still need to fire an engine on the far side of your orbit though which makes it more difficult as it still needs to be able to propel itself (while surviving the acceleration)
Well surviving the acceleration is trivial. I figured a 50km track in the post up above, in 50km you can accelerate up to lunar orbit velocities at just 1g of constant acceleration. So if your probe can survive sitting still on earth, it can survive accelerating at that speed.
You’re right though, you do need a small amount of thrust when you reach the top of your arc, but really not much. 50 m/s of DeltaV would do just fine. In other words, opening a can of compressed air would basically do it.
Or alternatively, you could use a mechanical system; you could have the vehicle (basically a rail cart) separate from the cargo with a powerful spring, pushing the cargo up, and the cart down. That mechanical system is also more effective the higher the apogee is, so if you launched the vehicle into a higher, more elliptical lunar orbit, that small push at the top pulls your low end of the orbit up much higher.
Ah, I was thinking more of a spinlaunch thing. Yours would make more sense, but would require a fuckton of industry in space or on the moon to have it work. I wonder how much more effective a self contained spinlaunch style thing would be on the moon.
Yeah, the application kind of assumes a lot of industry though. I mean if there isn’t a lot of industry, what are you shipping off the moon? But still, 50 km of rail is a lot, but it’s far less than the 325,000 km of tether that a space elevator would need…
Spin launch would definitely be feasible for some cargo, theoretically it would be a bit easier in vacuum, though that would probably also present other challenges. However, with a reasonably sized spin launch system (like the size of a 4 story apartment building), the payload needs to handle forces around 3000 Gs (which is a lot even for cargo). Unfortunately, you’d need to go larger for lower G force. So this also requires a lot of industry.
You still need to fire an engine on the far side of your orbit though which makes it more difficult as it still needs to be able to propel itself (while surviving the acceleration)
Well surviving the acceleration is trivial. I figured a 50km track in the post up above, in 50km you can accelerate up to lunar orbit velocities at just 1g of constant acceleration. So if your probe can survive sitting still on earth, it can survive accelerating at that speed.
You’re right though, you do need a small amount of thrust when you reach the top of your arc, but really not much. 50 m/s of DeltaV would do just fine. In other words, opening a can of compressed air would basically do it.
Or alternatively, you could use a mechanical system; you could have the vehicle (basically a rail cart) separate from the cargo with a powerful spring, pushing the cargo up, and the cart down. That mechanical system is also more effective the higher the apogee is, so if you launched the vehicle into a higher, more elliptical lunar orbit, that small push at the top pulls your low end of the orbit up much higher.
Ah, I was thinking more of a spinlaunch thing. Yours would make more sense, but would require a fuckton of industry in space or on the moon to have it work. I wonder how much more effective a self contained spinlaunch style thing would be on the moon.
Yeah, the application kind of assumes a lot of industry though. I mean if there isn’t a lot of industry, what are you shipping off the moon? But still, 50 km of rail is a lot, but it’s far less than the 325,000 km of tether that a space elevator would need…
Spin launch would definitely be feasible for some cargo, theoretically it would be a bit easier in vacuum, though that would probably also present other challenges. However, with a reasonably sized spin launch system (like the size of a 4 story apartment building), the payload needs to handle forces around 3000 Gs (which is a lot even for cargo). Unfortunately, you’d need to go larger for lower G force. So this also requires a lot of industry.