Lunar produced fuel lifted to EML depots & LEO
Lunar fuel to LEO? Eh, maybe and maybe not.
But you're still talking about tactics. You need to tie those tactics into the strategy and to do that you have to keep thinking about the goal.
Quote from: Bill White on 05/31/2011 05:10 amLunar fuel to LEO? Eh, maybe and maybe not.Yes, only if its cheaper than launch.
Quote from: Proponent on 05/31/2011 04:16 amQuote from: Bill White on 05/31/2011 04:13 amMaybe Jeff Greason and Paul Spudis should talk about this:QuoteThe second half of the talk is the presents a strategy: hopping from body to body with the primary objective of reducing the cost of future hops by producing propellant from local resources.Lunar propellant would seem the fastest and easiest opportunity for using local resources for making propellant.I agree. Greason doesn't mention Spudis during the talk, but he must be aware of the Spudis & Lavoie proposal, and I imagine he's thinking along those lines.One thing I'm not sure about is whether lunar propellant could be cheap enough to enable human exploration by NASA on NASA's current budget, as Greason asserts. But I think looking into the possibility ought to be a top priority.<snip>Therefore, maybe the best way to accomplish Greason's vision would be for the US Congress to fund an EML Gateway depot (since travel between EML-1 and EML-2 requires only modest delta v choosing either/or up front is not necessary).
Quote from: Bill White on 05/31/2011 04:13 amMaybe Jeff Greason and Paul Spudis should talk about this:QuoteThe second half of the talk is the presents a strategy: hopping from body to body with the primary objective of reducing the cost of future hops by producing propellant from local resources.Lunar propellant would seem the fastest and easiest opportunity for using local resources for making propellant.I agree. Greason doesn't mention Spudis during the talk, but he must be aware of the Spudis & Lavoie proposal, and I imagine he's thinking along those lines.One thing I'm not sure about is whether lunar propellant could be cheap enough to enable human exploration by NASA on NASA's current budget, as Greason asserts. But I think looking into the possibility ought to be a top priority.
Maybe Jeff Greason and Paul Spudis should talk about this:QuoteThe second half of the talk is the presents a strategy: hopping from body to body with the primary objective of reducing the cost of future hops by producing propellant from local resources.Lunar propellant would seem the fastest and easiest opportunity for using local resources for making propellant.
The second half of the talk is the presents a strategy: hopping from body to body with the primary objective of reducing the cost of future hops by producing propellant from local resources.
Look, Let's be completely honest here. Space settlement will not occur until launch costs become comparable to commuter flight costs and the risk assessment profile for companies backing such endevors (sic) likewise, becomes comparable to air craft travel. Either this has to happen, or some form of profit making process that will provide either a product or service at a vastly reduced production cost, would have to be found, that could only be provided in space.
Quote from: QuantumG on 05/31/2011 05:11 amQuote from: Bill White on 05/31/2011 05:10 amLunar fuel to LEO? Eh, maybe and maybe not.Yes, only if its cheaper than launch.I am partial to momentum exchange tethers. Use LEO tethers to catch in bound lunar fuel payloads (thereby raising the orbital energy of the LEO tethers) and later transfer that momentum to outbound supplies.
I'm partial to NASA saying "we need propellant in LEO", with some sort of anchor tenant guarantee, and letting the best minds in the industry dedicate their livelihood to providing it.Oh look: http://www.gpo.gov/fdsys/pkg/FR-2011-05-25/html/2011-10917.htm
1812.7000 Anchor tenancy contracts. (a) Section 401 of the Commercial Space Competitiveness Act, 15 U.S.C. 5806, allows NASA, subject to appropriations, to enter into multi-year anchor tenancy contracts for the purchase of a good or service if the Administrator determines that-- (1) The good or service meets the mission requirements of the National Aeronautics and Space Administration; (2) The commercially procured good or service is cost effective; (3) The good or service is procured through a competitive process; (4) Existing or potential customers for the good or service other than the United States Government have been specifically identified; (5) The long-term viability of the venture is not dependent upon a continued Government market or other nonreimbursable Government support; and (6) Private capital is at risk in the venture.
"Greason essentially saying NewSpace can do NASA's mission at lower cost to the taxpayers?" Is a fallacy. It's not about saving a billion or 20 years, its about mission success and astronaut safety.
No one ever says "what is the President's vision for how to get people transported from New York to San Jose?", because it is not the government which does that...
Let's be completely honest here.
However, IMHO, LEO depots have no point (no purpose or function) without missions. Without actual BEO missions, a LEO depot truly is a bridge to nowhere.
I am very doubtful that a majority of Congress believes that in their hearts and therefore when it comes time to write checks they will not vote appropriations that are consistent with the goal of space settlement.
[W]hat Greason is pointing out is that there's no concurrency of planning, which is what a strategy needs. * * *There is no strategy for the whole enchilada of colonization.
(a) Section 401 of the Commercial Space Competitiveness Act, 15 U.S.C. 5806, allows NASA, subject to appropriations, to enter into multi-year anchor tenancy contracts for the purchase of a good or service if the Administrator determines that --
Humans won't settle space. It's time to forget about this silly, unrealistic dream, which is just a 1950s version of frontier romance, IMO.* * *Also, there is no settlement if people don't stay permanently and reproduce.
However I believe that whether our species should make the attempt to become spacefaring, or not, is an existential question without a definitive right or wrong answer.
Humans won't settle space. It's time to forget about this silly, unrealistic dream, which is just a 1950s version of frontier romance, IMO.Humans cannot settle space because we cannot live in space. Yes, it's true.1) Everything we need to survive on the ISS has to be brought up from Earth, even the air they breathe. 2) And in 6 months of a single expedition, astronauts pick up the equivalent of a lifetime of radiation exposure on Earth (and it would be much worse in deep space: from the 24 Apollo astronauts who ventured beyond the Van Allen belt, how many died of cancer? Several, IIRC, and one, Swigert, quite quickly and unexpectedly!).People still have this wrong 1950s romantic vision of space. It's time to throw this away. Space is incredibly hostile to human life. Much more so than anywhere on Earth. In fact, we would be much better off settling the Antarctic and the Ocean floor, which are both less hostile. Living inside the Chernobyl or Fukushima exclusion zone is also far less dangerous than in outer space. And yet, nobody is settling Antarctica, the Ocean floor and the exclusion zones (a few exceptions notwithstanding).Also, there is no settlement if people don't stay permanently and reproduce.3) And human reproduction in space is unproven (there are good scientific reasons to suspect that human embryogenesis requires approx 1g to function correctly. If ever a female astronaut gets pregnant in space and the resulting child is stillborn or, worse, has a congenital malformation, then that will likely be the death-knell of any further settlement dream, for good, IMO).
Humans won't settle space. It's time to forget about this silly, unrealistic dream, which is just a 1950s version of frontier romance, IMO.Humans cannot settle space because we cannot live in space. Yes, it's true. Everything we need to survive on the ISS has to be brought up from Earth, even the air they breathe. And in 6 months of a single expedition, astronauts pick up the equivalent of a lifetime of radiation exposure on Earth (and it would be much worse in deep space: from the 24 Apollo astronauts who ventured beyond the Van Allen belt, how many died of cancer? Several, IIRC, and one, Swigert, quite quickly and unexpectedly!).People still have this wrong 1950s romantic vision of space. It's time to throw this away. Space is incredibly hostile to human life. Much more so than anywhere on Earth. In fact, we would be much better off settling the Antarctic and the Ocean floor, which are both less hostile. Living inside the Chernobyl or Fukushima exclusion zone is also far less dangerous than in outer space. And yet, nobody is settling Antarctica, the Ocean floor and the exclusion zones (a few exceptions notwithstanding).Also, there is no settlement if people don't stay permanently and reproduce. And human reproduction in space is unproven (there are good scientific reasons to suspect that human embryogenesis requires approx 1g to function correctly. If ever a female astronaut gets pregnant in space and the resulting child is stillborn or, worse, has a congenital malformation, then that will likely be the death-knell of any further settlement dream, for good, IMO).
Quote from: aquanaut99 on 05/31/2011 05:08 pmHumans won't settle space. It's time to forget about this silly, unrealistic dream, which is just a 1950s version of frontier romance, IMO....If what you say is true, we should never have left the oceans.
Humans won't settle space. It's time to forget about this silly, unrealistic dream, which is just a 1950s version of frontier romance, IMO....
So, once again, only religious-type argument. No scientific need to settle space...I reiterate: It is quite possible that humans cannot reproduce off-Earth.
If so, then space settlement is forever out of the question. Nothing you can argue will change that fact....