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Nibb31

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  1. Nibb31
    I'm European, and I agree. The ESM is too small to carry enough dV for a standalone mission, and too heavy to use for a simple reentry vehicle for BEO missions. Its design is constrained by the Constellation mission profile: 21 days and enough dV for a TEI burn, both of which are useless in Orion's current envisione role. Even the CM is both too small for long duration flights and too big to be a simple reentry capsule. For any meaningful mission, Orion needs an EUS and a hab module. Orion would have been better off either with an ACES or EUS-based service module or a simple cut-down SM like the one fitted to CST-100. Actually, CST-100 would probably be a better match for Orion's exploration role than Orion. Attach a hab module to a refuelable ACES-based EUS-SM and you have a reusable space-only exploration vehicle. Send crew to dock with a CST-100 and you can go anywhere in the solar system.
  2. Nibb31
    The delay with the Moon is negligeable, and teleoperating is pointless with more autonomous robots. It actually offers barely more possibilities than the ISS, but at a much higher cost.
  3. Nibb31
    My chip is with blind followers who take everything that Musk says at face value. Musk says a lot of things. A lot of his vision of the future is wishful thinking. Some of his ideas come to fruition, some of them take the long road, and some turn out to be not so good ideas when confronted with reality. The same is true for Bezos, Boeing, and Airbus to some extent, although for some reason, Musk has a fanboy audience that always gives him a free pass and seems to lose all critical thought for anything that he says. In my book, skepticism is healthy. The loss of critical thought is a mark of cultism. There is no good or bad or right or wrong in nature. Stuff happens because of reasons. I believe in chaos (theory) and causality more than in sci-fi-dream-driven fanboism. If we become a spacefaring civilization one day, it won't be because a bunch of followers believe in Musk's personal vision, but because the cultural, economical, and social reasons for our civilization to branch out into space will be reunited.
  4. Nibb31
    It's vice-versa actually. A colony implies settlement: moving in with your family and raising children. Places like oil rigs or research outposts don't qualify as colonies, they are temporary work places.
  5. Nibb31
    Lol. Ask any academic if mathematics aren't something that can be argued about ! Besides, I'm not arguing about the formulas, I'm arguing about the numbers that you feed into them. Musk claimed that the reusable price of a Falcon 9 launch could go down to $10 million. He also claimed that FH would fly by 2015. Seriously, you can talk about Musk's vision and plans all you want, but when it comes to schedules and numbers, nobody takes him seriously. [snip]
  6. Nibb31
    BFR needs ISRU to come back. ISRU needs BFR for iterative development. So unless ISRU works perfectly on its first attempt, the first iterations of BFR to Mars will be left on the surface, and each BFR is going to be a quite expensive piece of machinery. This is why they should have used Red Dragon to develop and validate ISRU concepts.
  7. Nibb31
    The edge of the ice cap is no place to build a base. Remember what happened to Phoenix ?
  8. Nibb31
    Fair enough. ISRU is IMO the less mature technology in Musk's Mars plan (the other one is the long-duration life support for 100 people). We are talking about a TRL2 or 3, when you are going to need at least TRL8 if you want to rely on it for the return trip. We are pretty certain that there is water on Mars, but we have no idea how much there is, where are the best places to look, or how deep we need to dig. Without knowing those things, I don't see how SpaceX can design a device to capture that water. The task has to be split down into a number of subtasks: Prospecting Drilling Collecting Purifying Converting Storing It's going to require a lot trial and error to progressively develop techniques in each of these areas, and even more work to get it to work autonomously with low maintenance and high reliability in an extreme environment. Some of it can be done in a lab, but it has to be proven in the field at various scales before you can expect to refuel your ship and bring it back. It will necessarily require several iterations, and they will certainly need to survey multiple areas to find out which locations are easiest to exploit. Given that iterations will be constrained by synods and budgets, I don't see how this can be done in less than a decade or even two. This is where Red Dragon could have come in handy. It would have be useful to carry a series proof of concept experiments with a drill or a scraping device to dig into the regolith. Without Red Dragon, the only alternative is to send a full-blown unmanned BFR on a one-way trip, which is going to be much more expensive.
  9. Nibb31
    It still seems like a bad plan: - An incoming BFS would be pretty obvious to detect and probably to intercept to. - The BFS shown in Musk's presentation needs a BFB to take off again, a huge crane to restack the whole thing, and a rather big propellant farm.
  10. Nibb31
    Why not start a new thread on this ? Let's try to keep the SpaceX thread clean.
  11. Nibb31
    Assuming hyperloop is technically and economically feasible, which is far from a given.
  12. Nibb31
    Ignoring the totally made up numbers, that's a lot of assumption there. You keep on harping as if your Mars colony was totally self-sufficient with a million people from day one, attracting highly qualified people who are ready to spend $250.000 to relocate with their families as "farmers", "miners" or "space cowboys". It will take decades (if ever) to get to the point where living on mars is going to be cheap, comfortable, attractive, and safe. Decades during which everything will have to be shipped over 2 year synods for a huge costs. Decades during which all the technology will have to be developed on Earth. Decades of sending people to live in poor survival conditions while they supervise the construction of the colony. Decades of massive spending to keep those people alive with no return on investment. Decades of uncertainty about the goal of becoming a totally self-sufficient with a million people. As long as you ignore the economical, political, sociological, and technical realities of actually reaching that goal, your assumptions about how an already established colony would work are irrelevant. Now I really suggest that we stop derailing this thread, which is supposed to be keeping track of SpaceX, and move this colony discussion to another thread. It would be great if a friendly neighbourhood moderator could split this thread.
  13. Nibb31
    SpaceX is composed in majority of a young, enthusiastic, overworked, and underpaid workforce. I suspect the overoptimistic timelines and Mars plans has more to do with keeping them motivated.
  14. Nibb31
    No, and there aren't many of examples of heat shields that have been reused, period. CRS-11 reused the same Dragon as CRS-4, but a lot of systems, including the heatshield, were replaced. There is actually a lot of unproven technology in the BFR program, and all of these technologies have to work as designed. A non-exhaustive list: Low maintenance reusable heatshield Orbital cryo propellant refilling 6 month ECLSS (for 100 passengers) Composite tankage (with common bulkhead and internal header tanks) Cradle landing Flip-over manoeuver and propulsive landing Vacuum nozzles that can survive reentry and hypersonic flow Mars ISRU And then there is the entire economical, legal, and political environment to deal with. While a lot of this works on paper, we all know that the actual engineering is much more complicated. Things like SpaceX upper stage reuse, Falcon Heavy, or propulsive landing with Dragon 2 also seemed easy on paper, but proved more complicated once they were confronted with reality. Even F9 1st stage reuse, although technically proven, now has to prove to be economically viable, which is a whole different set of problems. The challenges are just as significant as the milestones that the Apollo program had identified for Moon shot to become possible: multiple day ECLSS, EVA, rendez-vous, docking, navigation, etc... These were all possible on paper, but required the Gemini program to develop the techniques, discover the pitfalls and workarounds, and prove that they were practical. Gemini was a significant effort that had to run in parallel with the Apollo development effort. If only one of the technologies required for BFR turns out to be a dead end, then the whole fundamental architecture is screwed.
  15. Nibb31
    Why are you asking this question when this is precisely what we have been talking about for the last couple of days ? Didn't you bother to read the last 15 pages of the thread ?
  16. Nibb31
    Platinum, which is commonly used as a candidate for asteroid mining, is used for two things: jewelry and catalytic converters for the automobile industry. The automobile industry is going to be moving away from internal combustion engines, making catalytic converters redundant, and the appeal of platinum jewelry is based on its rarity.
  17. Nibb31
    I was referring to the USA as being former colonies that became dominant. Spain and Portugal lost all domination before they lost their colonies. Actually at one point the state of Portugal was relocated to Brazil. There is no rule that expansion through colonization is always profitable. Besides, historical analogies do not apply. For one, colonization was mostly for political and economical profit with trade as a major incitation.
  18. Nibb31
    Like the USA? Or like Spain and Portugal?
  19. Nibb31
    You are aware that government colonization rarely ends well for the governments. In the past, invariably, the colonies that were built at a huge expense all end up demanding independence and breaking off from their mother country. A self-sufficient Mars colony isn't a great objective for a government to invest in.
  20. Nibb31
    A tiny incentive compared to a massive investment. If the ROI does not cover the investment, then it isn't an investment. So that doesn't work. Why would Mars biologists have more chance of discovering those things that Earth biologists ? Why couldn't a research lab on Earth be able to elaborate treatments for Mars patients ? Why would Monsanto or Pfizer invest in an R&D facility on Mars for 100 times the cost of an equivalent R&D facility in India or Malaysia ? Once. But how much time does it take to get to that point, while operating at a loss. You keep on claiming that like will be great once the colony reaches a critical mass. The problem is still the decades or centuries it takes to reach that critical mass. You can't just dump a million people on Mars. You need to build a city for millions of people, to grow it progressivement. In order to reach that critical mass, the effort needs to be both sustainable (not self-sustainable) and attractive (economically and in terms of quality of life) from the start, not after 100 years. You're still in your wild west fantasy.
  21. Nibb31
    How does that work ? SpaceX is only going to operate the transportation system. Once you're there, you're going to need some other arrangement. We have no idea who is going to run the colony or what the political system is going to be. In all likelihood, those who pay for it have the power, but nobody has any idea how the economics of keeping a million humans alive in a bubble is going to work. On Earth, utilities like power, water, communications for a city of 1 million, require a massive investment and people have to pay to use them. How do you finance an even bigger investment on Mars ? I have no idea, which is why I'm asking the question. I don't know how that can work. Highly qualified people are expensive to hire. Somebody has to pay them. They also have families and friends and they usually live in relative comfort compared to the less qualified members of society. So either you make them settlers and convince them to give up a comfortable life on Earth to move to Mars with their families, or you expect them to come back home to spend their expat money.
  22. Nibb31
    Who said under the sea ? The idea of ocean colonies in international waters has been floating around for a while (see what I did there?). Ever heard of Sealand ? Hey! Weren't we supposed to be talking about self-sustainence and closed-loop life support ? If we can have self-sustaining closed systems on Mars, why can't we use the same technologies on Earth to become a zero-emissions civilization as a solution to our global warming problem ? That might actually be a better use for such an investment. I contend that a multi trillion dollar Mars colony would disrupt the world's economy quite a bit too. My point is that there is no need for ocean colonies or self-sustaining dome cities in the Australian outback. So there is also no need for the same on Mars.
  23. Nibb31
    Wrong. America trades because it provides an outlet for its economy and produces a very significant part of its GDP. isn't Autarcy isn't an option. You tell me. Without trade, you can't fund imports. You can't provide an attractive environment for immigrants without a minimum of creature comforts. Guess what country doesn't trade. North Korea. They are pretty much self-sufficient and it's much more pleasant than Mars, but who wants to sell their house and go live there ?
  24. Nibb31
    Before you get thousands, you need to have one. Then two. You don't get from zero to millions in a fortnight. If you want your colony to grow to millions, it has to be successful with a hundred, otherwise you never get to a thousand. The difficulty isn't being successful once it has succeeded. The difficulty is succeeding. So you want free enterprise but you want a planned economy. You don't want capitalism but you do want competition. You want initial investment from Earth but you have nothing to export. How does that work exactly ?
  25. Nibb31
    There will be no such things as "farmers" or "miners" in a high-tech space colony. There will be technicians, employed by whoever invested to set up the food production facility. It's likely that the crops will be GMO especially engineered for the task and imported in order to maintain a proper revenue for Monsanto or whoever is providing them. Your idea of a Mars colony is way to influenced by some romantic vision of the American wild west. It will be nothing like that. You've never worked in a factory, have you ? There won't be any factory workers on Mars either. They are already disappearing on Earth. How do you get that massive upfront investment without capitalism ? Freedom is rather limited when you have to rely on artificial life support just to breath. ECLSS on a Mars colony will be expensive to run and probably a centralized utility, like power and water, that you either you will have to pay for, or your employer pays for you. Nothing is free in a resource-limited closed loop bubble. Sure, but you're not going to eradicate war or military spending, so you can pretty much forget that as a source of funding. It's not going to happen. In today's world, if you want to fund something, you borrow from the banks, but you've got to have a pretty compelling business case, especially if your expected ROI is in 100 years.
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