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Starship is significantly scaled down from their original plans. Despite being enormous, it's actually about the minimum viable size. Assuming there is the traf

by xoa 6y ago

Starship is significantly scaled down from their original plans. Despite being enormous, it's actually about the minimum viable size. Assuming there is the traffic to support one of course, there are actually a number of scaling advantages to greater size when using stainless steel as the construction material. So while it'd take a long while, SpaceX may well ultimately find it advantageous to do a larger Starship 2. Another area that humanity hasn't even gotten to the stage of considering yet would be dedicated interplanetary space transport craft. For now SpaceX is planning to just use Starships for getting out of gravity wells and getting between them. But the kind of cadence, $/kg, and sheer capacity Starship will enable also opens up the real option of permanent orbital assembly and maintenance facilities, and in turn the construction of spacecraft optimized purely for use outside of gravity wells (so much more emphasis on ISP vs thrust, no need to worry about aerodynamics, far less restriction on size, optimization for long time travel like potential synthetic gravity via spin, more radiation shielding, etc). No reason SpaceX couldn't lead the charge on that too in principle, though certain attractive forms of propulsion like anything using nuclear would probably necessitate more government involvement until/unless SpaceX can form their own mature government far down the road. Anyway, $100-200/kg (or less!) and huge volume/high cadence is so radically disruptive that it's kind of hard to predict how space will look a few decades down the line. It's going to be a wild thing to watch, with lots of opportunity.

systemvoltage 6y ago
> permanent orbital assembly Sorry not familiar with these plans - does this mean that we assemble a bigger rocket (by using earth based rockets) at ISS level orbits and then relaunch to another planet?
- NortySpock 6y ago
  I assume this is going to be not too much more than "we dock several components together in Earth orbit, then fly the whole thing where we want it to go" In theory this would work for anything that is permanently in vacuum, such as the NASA Lunar Gateway (though it's currently planned for lunar-orbit operations only), or some future low-Earth orbit station such as Gateway Station[1] or some sort of Venus, Mars, or Ceres orbital habitat. [1] https://gatewayspaceport.com/the-gateway/ https://gatewayspaceport.com/the-gateway/
m4rtink 6y ago
There are quite a few benefits of how current Starship has been designed and actually nicely demonstrates how cleverly though out the whole thing is! It goes between two places with at least some sort of atmosphere by default (or one with and on without for the Lunar variant) so while indeed dragging aerosurfaces with your in the vacuum of space might seem wasteful on the first look, you can save huge amounts of delta-v once you arrive at your destination due to atmospheric braking. A purely built for space vacuum only craft could be built to be much lighter but would also need to loose all that excess interplanetary speed with engine power alone, potentially negating the advantages quite a bit. There are, of course, various hybrid approaches: - the space only craft still could have some limited aerodynamics to do earocapture to orbit at the destination or at least do aerobraking from a "cheap" eccentric capture orbit - you could have a space only "hotel" ship on a cycler orbit and get passengers and cargo using Starship like "taxi" ships from a planet - a big complex space-only ship could have fancy high tech low thrust & high ISP engines that would not realistically fit on craft that needs to be fairly aerodynamic Also as for in space construction - indeed, it will enable really massive and efficient space structures, but we are not there yet space infrastructure wise. And Starships so far have shown how easily they can be made in their current form using very basic tech during their assembly, even compared to tech used for existing decades old expandable rockets! :) So no doubt eventually big efficient high tech in space cruisers will carry the most interplanetary traffic, it seems like Starship is a surprisingly good fit for the time being & for putting in place the building stones of that future. :)
cryptonector 6y ago
Yes, this. With orbital assembly you can have fewer engines (save on weight) all optimized for vacuum and no fairing or a super-minimal fairing (save on weight). Heck, you don't need orbital assembly for that. SpaceX could put in orbit a single- or two-engine starship with no landing legs and no heat shielding for transfers. Eventually they could decommission one such truck to make an orbital station. > Anyway, $100-200/kg (or less!) and huge volume/high cadence is so radically disruptive that it's kind of hard to predict how space will look a few decades down the line. It's going to be a wild thing to watch, with lots of opportunity. There might be so many satellites in orbit as to permanently disrupt astronomy on Earth, necessitating a fleet of replacements for the James Webb telescope.
- AstralStorm 6y ago
  Keeping stuff in space has a maintenance cost - both station keeping which can be relatively cheap, and maintenance for any space trash collisions. Most importantly, there is no commercial space station to move people and current starship test articles are not fitted for passenger transport nor low earth orbit rendezvous. It's a long road from even a properly working Starship towards this goal.
  - rbanffy 6y ago
    Maintenance for space junk collisions should be cheaper than landing and relaunching, and, if launching heavier things gets cheaper, we can afford making them less delicate.
- rbanffy 6y ago
  > Heck, you don't need orbital assembly for that. SpaceX could put in orbit a single- or two-engine starship with no landing legs and no heat shielding for transfers. That's SpaceX's lunar lander plan - a Starship that'd never need to come back to Earth except for refueling.

by xoa 6y ago

systemvoltage 6y ago

> permanent orbital assembly Sorry not familiar with these plans - does this mean that we assemble a bigger rocket (by using earth based rockets) at ISS level orbits and then relaunch to another planet?

NortySpock 6y ago
I assume this is going to be not too much more than "we dock several components together in Earth orbit, then fly the whole thing where we want it to go" In theory this would work for anything that is permanently in vacuum, such as the NASA Lunar Gateway (though it's currently planned for lunar-orbit operations only), or some future low-Earth orbit station such as Gateway Station[1] or some sort of Venus, Mars, or Ceres orbital habitat. [1] https://gatewayspaceport.com/the-gateway/ https://gatewayspaceport.com/the-gateway/

m4rtink 6y ago

There are quite a few benefits of how current Starship has been designed and actually nicely demonstrates how cleverly though out the whole thing is! It goes between two places with at least some sort of atmosphere by default (or one with and on without for the Lunar variant) so while indeed dragging aerosurfaces with your in the vacuum of space might seem wasteful on the first look, you can save huge amounts of delta-v once you arrive at your destination due to atmospheric braking. A purely built for space vacuum only craft could be built to be much lighter but would also need to loose all that excess interplanetary speed with engine power alone, potentially negating the advantages quite a bit. There are, of course, various hybrid approaches: - the space only craft still could have some limited aerodynamics to do earocapture to orbit at the destination or at least do aerobraking from a "cheap" eccentric capture orbit - you could have a space only "hotel" ship on a cycler orbit and get passengers and cargo using Starship like "taxi" ships from a planet - a big complex space-only ship could have fancy high tech low thrust & high ISP engines that would not realistically fit on craft that needs to be fairly aerodynamic Also as for in space construction - indeed, it will enable really massive and efficient space structures, but we are not there yet space infrastructure wise. And Starships so far have shown how easily they can be made in their current form using very basic tech during their assembly, even compared to tech used for existing decades old expandable rockets! :) So no doubt eventually big efficient high tech in space cruisers will carry the most interplanetary traffic, it seems like Starship is a surprisingly good fit for the time being & for putting in place the building stones of that future. :)

cryptonector 6y ago

Yes, this. With orbital assembly you can have fewer engines (save on weight) all optimized for vacuum and no fairing or a super-minimal fairing (save on weight). Heck, you don't need orbital assembly for that. SpaceX could put in orbit a single- or two-engine starship with no landing legs and no heat shielding for transfers. Eventually they could decommission one such truck to make an orbital station. > Anyway, $100-200/kg (or less!) and huge volume/high cadence is so radically disruptive that it's kind of hard to predict how space will look a few decades down the line. It's going to be a wild thing to watch, with lots of opportunity. There might be so many satellites in orbit as to permanently disrupt astronomy on Earth, necessitating a fleet of replacements for the James Webb telescope.

AstralStorm 6y ago
Keeping stuff in space has a maintenance cost - both station keeping which can be relatively cheap, and maintenance for any space trash collisions. Most importantly, there is no commercial space station to move people and current starship test articles are not fitted for passenger transport nor low earth orbit rendezvous. It's a long road from even a properly working Starship towards this goal.
- rbanffy 6y ago
  Maintenance for space junk collisions should be cheaper than landing and relaunching, and, if launching heavier things gets cheaper, we can afford making them less delicate.
rbanffy 6y ago
> Heck, you don't need orbital assembly for that. SpaceX could put in orbit a single- or two-engine starship with no landing legs and no heat shielding for transfers. That's SpaceX's lunar lander plan - a Starship that'd never need to come back to Earth except for refueling.