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Didn't the Saturn 5 have a similar mass budget as the Starship? I am guessing there is some major caveat to it.

bryanlarsen 3y ago
They might be comparable without refueling, but Starship utilizes refueling to massively increase it's deep space mass budget.
- pavon 3y ago
  This is the huge difference. Apollo missions used two launches of the Saturn V - one for the crew capsule and one for the lunar lander, which rendezvoused in orbit. Artemis is planning on using one SLS launch for the crew capsule, and an estimated 8-16 Starship launches for the lunar lander and refueling.
  - saratogacx 3y ago
    That isn't how the Apollo missions worked. They put the command module, service module and the LEM on a single Saturn 5[1]. Once in space, the command+service module would need to turn around and dock with the LEM before heading off to the moon. https://www.nasa.gov/history/diagrams/apollo.html https://www.nasa.gov/history/diagrams/apollo.html 1: https://www.nasa.gov/wp-content/uploads/static/history/diagrams/ad003.gif https://www.nasa.gov/wp-content/uploads/static/history/diagr...
  - DarmokJalad1701 3y ago
    > Apollo missions used two launches of the Saturn V - one for the crew capsule and one for the lunar lander, which rendezvoused in orbit. That was a concept called "Earth Orbit Rendezvous" which was discarded early on during the Apollo program in favor of "Lunar Orbit Rendezvous" where the Command and Service Module (CSM) and the Lunar Module (LM) was launched on a single Saturn V. You can see this in the movie Apollo 13.
  - tekla 3y ago
    > Apollo missions used two launches of the Saturn V - one for the crew capsule and one for the lunar lander, What? Have you watched any Apollo mission media ever? Watch Apollo 13 the movie at least and get the most basics of facts straight.
- nativeit 3y ago
  Starship might utilize refueling. So far it hasn’t done anything of the sort.
  - avhon1 3y ago
    Starship must utilize refueling. It can't get to, land on, and return from the moon without it.
GMoromisato 3y ago
No, it did not. Starship gets refueled in orbit (by a fleet of Saturn V-class rockets). A Saturn V could put about 8 metric tons on the lunar surface. With refueling, Starship can land 100 metric tons on the moon.
- sixothree 3y ago
  How many fuel launches are required for that?
  - agar 3y ago
    That's a matter of some debate. Somewhere between 6 and 12, I believe, is the range. SpaceX plans to stretch the second stage to increase fuel carrying capacity for tanker flights, so the actual number is TBD until both the revised Starship and its engines (Raptor 3) are built and tested.
    - datadrivenangel 3y ago
      It might take up to 20... NASA doesn't actually know / admit that it knows.
  - imtringued 3y ago
    It depends on how many Starships you can launch simultaneously, because the time the fuel depot spends in orbit determines how much fuel is lost to boil-off. If you have a serial launch architecture, assuming reusability, refuling and relaunching, then the upper bound is around 20 launches. Even with expendable Starships, this is still cheaper than SLS, but not by much... This is why reusability is critical to the mission.
    - sixothree 3y ago
      I guess that means boil off would affect missions to the moon and mars as well.
giantrobot 3y ago
The Saturn V could get a lot of mass to LEO but most of that mass was fuel to get from LEO to the surface of the Moon. A design caveat of SpaceX Starship (a design feature that's yet to be demonstrated/proven) is refueling in LEO. So the Starship gets a bunch of payload mass to LEO, refuels, and then heads to the Moon. For Mars it would need to refuel on Mars to get back to Earth. It's the refueling that potentially gets a huge usable payload to the Moon. A second Starship whose only payload is fuel would launch with the first and they'd rendezvous and transfer fuel. Ostensibly if something went wrong with the refuel rendezvous the payload (or personnel) carrier would still be able to abort back to Earth.

They might be comparable without refueling, but Starship utilizes refueling to massively increase it's deep space mass budget.

pavon 3y ago
This is the huge difference. Apollo missions used two launches of the Saturn V - one for the crew capsule and one for the lunar lander, which rendezvoused in orbit. Artemis is planning on using one SLS launch for the crew capsule, and an estimated 8-16 Starship launches for the lunar lander and refueling.
- saratogacx 3y ago
  That isn't how the Apollo missions worked. They put the command module, service module and the LEM on a single Saturn 5[1]. Once in space, the command+service module would need to turn around and dock with the LEM before heading off to the moon. https://www.nasa.gov/history/diagrams/apollo.html https://www.nasa.gov/history/diagrams/apollo.html 1: https://www.nasa.gov/wp-content/uploads/static/history/diagrams/ad003.gif https://www.nasa.gov/wp-content/uploads/static/history/diagr...
- DarmokJalad1701 3y ago
  > Apollo missions used two launches of the Saturn V - one for the crew capsule and one for the lunar lander, which rendezvoused in orbit. That was a concept called "Earth Orbit Rendezvous" which was discarded early on during the Apollo program in favor of "Lunar Orbit Rendezvous" where the Command and Service Module (CSM) and the Lunar Module (LM) was launched on a single Saturn V. You can see this in the movie Apollo 13.
- tekla 3y ago
  > Apollo missions used two launches of the Saturn V - one for the crew capsule and one for the lunar lander, What? Have you watched any Apollo mission media ever? Watch Apollo 13 the movie at least and get the most basics of facts straight.
nativeit 3y ago
Starship might utilize refueling. So far it hasn’t done anything of the sort.
- avhon1 3y ago
  Starship must utilize refueling. It can't get to, land on, and return from the moon without it.

GMoromisato 3y ago

No, it did not. Starship gets refueled in orbit (by a fleet of Saturn V-class rockets). A Saturn V could put about 8 metric tons on the lunar surface. With refueling, Starship can land 100 metric tons on the moon.

sixothree 3y ago
How many fuel launches are required for that?
- agar 3y ago
  That's a matter of some debate. Somewhere between 6 and 12, I believe, is the range. SpaceX plans to stretch the second stage to increase fuel carrying capacity for tanker flights, so the actual number is TBD until both the revised Starship and its engines (Raptor 3) are built and tested.
  - datadrivenangel 3y ago
    It might take up to 20... NASA doesn't actually know / admit that it knows.
- imtringued 3y ago
  It depends on how many Starships you can launch simultaneously, because the time the fuel depot spends in orbit determines how much fuel is lost to boil-off. If you have a serial launch architecture, assuming reusability, refuling and relaunching, then the upper bound is around 20 launches. Even with expendable Starships, this is still cheaper than SLS, but not by much... This is why reusability is critical to the mission.
  - sixothree 3y ago
    I guess that means boil off would affect missions to the moon and mars as well.

giantrobot 3y ago

The Saturn V could get a lot of mass to LEO but most of that mass was fuel to get from LEO to the surface of the Moon. A design caveat of SpaceX Starship (a design feature that's yet to be demonstrated/proven) is refueling in LEO. So the Starship gets a bunch of payload mass to LEO, refuels, and then heads to the Moon. For Mars it would need to refuel on Mars to get back to Earth. It's the refueling that potentially gets a huge usable payload to the Moon. A second Starship whose only payload is fuel would launch with the first and they'd rendezvous and transfer fuel. Ostensibly if something went wrong with the refuel rendezvous the payload (or personnel) carrier would still be able to abort back to Earth.