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When the project management at the top level is committed to unrealistic deadlines, it makes realistic engineering hard at all lower levels. Given that nature

When the project management at the top level is committed to unrealistic deadlines, it makes realistic engineering hard at all lower levels. Given that nature cannot be fooled, this combination of factors tends toward failure.

nickff 6y ago
Kennedy committed to reaching the moon within 8.75 years in March of 1961, when the USA had a total of 15 minutes of experience in human spaceflight, all suborbital. They hadn't even decided what architecture would get them there. They succeeded, and this is far less ambitious.
- Retric 6y ago
  The Apollo program also killed people. https://en.wikipedia.org/wiki/Apollo_1 https://en.wikipedia.org/wiki/Apollo_1 Taking risks is reasonable, but in the end this is still a vanity project. IMO, figuring out how to do self sustaining spaceships / habitats is much more useful long term than going back to the moon using giant chemical rockets, stored food and oxygen etc. Even just orbiting Mars and coming back without landing would be a new achievement.
  - nickff 6y ago
    Well, if you want to know whether it's worth the risk, I think the best people to ask are the astronauts, and they are chomping at the bit to go. As far as I can see, there isn't much point to going around Mars just to go. You could just go to a high Earth orbit (or Lagrange point), and gain similar experience, with better communication. The ISS has spent 20 years in low-earth orbit; we're not going to learn much more from it or a similar station.
    - Retric 6y ago
      Apollo 8 and 10 both went to the moon without landing, doing that on a multiple year mission does seem wasteful. However, there are a host of things to test. From an engineering perspective going to mars orbit means far less sunlight which means a host of new problems. An engine and fuel system to get there would be new and could also be used to send a lander for future missions. IMO, the Moon might be closer, but Mars is a much better target for long term colonization due to an atmosphere, shorter day, higher gravity, etc.
      - unnouinceput 6y ago
        You meant lower gravity, right? Mars is smaller then Earth.
        austinprete 6y ago
        Sounded like his comparisons were for Mars vs. the moon.
      - squarefoot 6y ago
        The Moon could be the starting point for Mars colonization. Also, it would make a huge difference if the new Moon missions took advantage of the ISS, which the Apollo missions couldn't count on. One thing is bringing all crew, supplies and equipment from Earth in one trip, and a whole different thing is sending everything on/around the ISS using unmanned cargo missions, then assemble the lunar mission ships up there and send the Moon astronauts when necessary. In other words: Earth<->ISS, then ISS<->Moon<->Mars and/or ISS<->Mars.
        Retric 6y ago
        For Mars you want people to go up last so they minimize the time spent in zero g. Docking supplies on the ISS is also pointless. The ISS is not in a useful orbit for a Mars trip and whatever your sending there can make the trip in the same thing you send into orbit. Trying to shoehorn in the ISS just make the trip more expensive and complex.
        nickik 6y ago
        I agree that Mars is better, but Starship is for Mars. If NASA pays for development, that is moving much closer.
  - nickik 6y ago
    Chemical rocket are the right technology for the inner solar system. And big one and specially reusable have advantages and we know nothing that could potentially be cheaper. Part of this whole moon approach is absolutely about sustaining the long term. Have you ever read the Artemis program concepts? It is very much about using commercial capability to develop moon resources. You can't start with producing food, if you make the system depended on that it will fail. One you can actually land on the moon or mars with SIGNIFICANT payloads you can actually start to test out system for large scale food growing and things like that.
    - Retric 6y ago
      Getting to Mars on chemical rockets is not that bad, especially if you can accept a launch window every 15 years. Getting people to and back from low Mars orbit with chemical rockets on a more flexible schedule takes a lot more fuel. It’s clearly viable, but for that kind of DeltaV across such a long trip, solar powered Ion thrusters have several significant advantages. As to growing food, for on a single mission it’s not that critical, but if you’re sending several missions to Mars unused supplies from one mission can be used on the next mission. Further, the difference between survival and comfort adds up to a lot of food.
      - Tuna-Fish 6y ago
        Cheap Mars launch windows are every 26 months, not 15 years.
        Retric 6y ago
        Cheap is relative, Earth years and Mars years don’t evenly divide, so the 26 month cycle is fairly good but not optimal if your willing to wait.
      - nickik 6y ago
        You can go every 26 month. If you can produce fuel on Mars going back is way easier then going from Earth to Mars. You don't go from Mars Orbit, you take of from the surface directly to earth where you aerobrake. No Orbit operation on Mars needed. > It’s clearly viable, but for that kind of DeltaV across such a long trip, solar powered Ion thrusters have several significant advantages. Not really. The only potential use for ion thrusters is for cargo transport that is not time depended. If you do that you need to figure out how to do the landing, so the complexity is just higher. The thrust is just to low compared to a few powerful chemical engines. If you can refuel in earth orbit for cheap you are gone be way better off with chemical. If you move on from chemical, nuclear thermal is by far the best option. Food is really not the problem. The mass of food needed for humans is pretty small. Clearly you want to produce food on Mars eventually but its not a priority for the first 5 to 10 years. Refuel on Mars is by far the biggest mass saver.
- rakoo 6y ago
  The US also devoted up to 4.5% of its federal budget for the task (https://storage.googleapis.com/dbc2017/April/April%2011%20NASA%20budget.png https://storage.googleapis.com/dbc2017/April/April%2011%20NA...) when the current budget is half of a percent. The priorities are definitely not the same
  - nickik 6y ago
    Whenever somebody uses % of budget as an argument I just shake my head.
    - rakoo 6y ago
      % of budget is a good proxy to estimate intentions
      - nickik 6y ago
        You don't buy rockets with intentions.
        rakoo 6y ago
        You don't go to the moon in less 4 years if you don't really commit to it, especially if you haven't been there for 40 years
        nickik 6y ago
        Committing to it could be done within the NASA budget. This currently is not even the majority of the NASA budget. Its only bit more then half of the human budget. So the argument that 'you can only do this when the government gives NASA military budget' is just nonsense.

nickff 6y ago

Kennedy committed to reaching the moon within 8.75 years in March of 1961, when the USA had a total of 15 minutes of experience in human spaceflight, all suborbital. They hadn't even decided what architecture would get them there. They succeeded, and this is far less ambitious.

Retric 6y ago
The Apollo program also killed people. https://en.wikipedia.org/wiki/Apollo_1 https://en.wikipedia.org/wiki/Apollo_1 Taking risks is reasonable, but in the end this is still a vanity project. IMO, figuring out how to do self sustaining spaceships / habitats is much more useful long term than going back to the moon using giant chemical rockets, stored food and oxygen etc. Even just orbiting Mars and coming back without landing would be a new achievement.
- nickff 6y ago
  Well, if you want to know whether it's worth the risk, I think the best people to ask are the astronauts, and they are chomping at the bit to go. As far as I can see, there isn't much point to going around Mars just to go. You could just go to a high Earth orbit (or Lagrange point), and gain similar experience, with better communication. The ISS has spent 20 years in low-earth orbit; we're not going to learn much more from it or a similar station.
  - Retric 6y ago
    Apollo 8 and 10 both went to the moon without landing, doing that on a multiple year mission does seem wasteful. However, there are a host of things to test. From an engineering perspective going to mars orbit means far less sunlight which means a host of new problems. An engine and fuel system to get there would be new and could also be used to send a lander for future missions. IMO, the Moon might be closer, but Mars is a much better target for long term colonization due to an atmosphere, shorter day, higher gravity, etc.
    - unnouinceput 6y ago
      You meant lower gravity, right? Mars is smaller then Earth.
      - austinprete 6y ago
        Sounded like his comparisons were for Mars vs. the moon.
    - squarefoot 6y ago
      The Moon could be the starting point for Mars colonization. Also, it would make a huge difference if the new Moon missions took advantage of the ISS, which the Apollo missions couldn't count on. One thing is bringing all crew, supplies and equipment from Earth in one trip, and a whole different thing is sending everything on/around the ISS using unmanned cargo missions, then assemble the lunar mission ships up there and send the Moon astronauts when necessary. In other words: Earth<->ISS, then ISS<->Moon<->Mars and/or ISS<->Mars.
      - Retric 6y ago
        For Mars you want people to go up last so they minimize the time spent in zero g. Docking supplies on the ISS is also pointless. The ISS is not in a useful orbit for a Mars trip and whatever your sending there can make the trip in the same thing you send into orbit. Trying to shoehorn in the ISS just make the trip more expensive and complex.
      - nickik 6y ago
        I agree that Mars is better, but Starship is for Mars. If NASA pays for development, that is moving much closer.
- nickik 6y ago
  Chemical rocket are the right technology for the inner solar system. And big one and specially reusable have advantages and we know nothing that could potentially be cheaper. Part of this whole moon approach is absolutely about sustaining the long term. Have you ever read the Artemis program concepts? It is very much about using commercial capability to develop moon resources. You can't start with producing food, if you make the system depended on that it will fail. One you can actually land on the moon or mars with SIGNIFICANT payloads you can actually start to test out system for large scale food growing and things like that.
  - Retric 6y ago
    Getting to Mars on chemical rockets is not that bad, especially if you can accept a launch window every 15 years. Getting people to and back from low Mars orbit with chemical rockets on a more flexible schedule takes a lot more fuel. It’s clearly viable, but for that kind of DeltaV across such a long trip, solar powered Ion thrusters have several significant advantages. As to growing food, for on a single mission it’s not that critical, but if you’re sending several missions to Mars unused supplies from one mission can be used on the next mission. Further, the difference between survival and comfort adds up to a lot of food.
    - Tuna-Fish 6y ago
      Cheap Mars launch windows are every 26 months, not 15 years.
      - Retric 6y ago
        Cheap is relative, Earth years and Mars years don’t evenly divide, so the 26 month cycle is fairly good but not optimal if your willing to wait.
    - nickik 6y ago
      You can go every 26 month. If you can produce fuel on Mars going back is way easier then going from Earth to Mars. You don't go from Mars Orbit, you take of from the surface directly to earth where you aerobrake. No Orbit operation on Mars needed. > It’s clearly viable, but for that kind of DeltaV across such a long trip, solar powered Ion thrusters have several significant advantages. Not really. The only potential use for ion thrusters is for cargo transport that is not time depended. If you do that you need to figure out how to do the landing, so the complexity is just higher. The thrust is just to low compared to a few powerful chemical engines. If you can refuel in earth orbit for cheap you are gone be way better off with chemical. If you move on from chemical, nuclear thermal is by far the best option. Food is really not the problem. The mass of food needed for humans is pretty small. Clearly you want to produce food on Mars eventually but its not a priority for the first 5 to 10 years. Refuel on Mars is by far the biggest mass saver.
rakoo 6y ago
The US also devoted up to 4.5% of its federal budget for the task (https://storage.googleapis.com/dbc2017/April/April%2011%20NASA%20budget.png https://storage.googleapis.com/dbc2017/April/April%2011%20NA...) when the current budget is half of a percent. The priorities are definitely not the same
- nickik 6y ago
  Whenever somebody uses % of budget as an argument I just shake my head.
  - rakoo 6y ago
    % of budget is a good proxy to estimate intentions
    - nickik 6y ago
      You don't buy rockets with intentions.
      - rakoo 6y ago
        You don't go to the moon in less 4 years if you don't really commit to it, especially if you haven't been there for 40 years
        nickik 6y ago
        Committing to it could be done within the NASA budget. This currently is not even the majority of the NASA budget. Its only bit more then half of the human budget. So the argument that 'you can only do this when the government gives NASA military budget' is just nonsense.