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Space Science Technology

Space Is (Not) the Place, Says Professor 376

snoop.daub writes "A while back, we discussed UCSD professor Tom Murphy's post about the limits on growth in energy use and economies. Partly in reaction to Slashdot's response (and my own writeup!), he's back with a new post arguing that space is not a solution to enable continued growth. There's a lot of good stuff in here about public misconceptions regarding the difficulty of space travel and the like; again definitely worth the read."
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Space Is (Not) the Place, Says Professor

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  • Do the math, indeed! (Score:2, Interesting)

    by Baldrson ( 78598 ) * on Tuesday October 18, 2011 @07:35PM (#37756538) Homepage Journal
    This guy is ridiculously illiterate. Do the math [mike-combs.com], indeed!

    The one area the US government was prohibited from competing with private sector companies in by the act that established NASA was satellite communications.

    That relegated other areas of economic development of space to a communist model of government run services. It is no surprise, then, that the Soviets were more efficient in developing launch capabilities and indeed manned space presence -- they were professional communists: If their communist bureaucracies didn't function, they didn't eat. Contrast that with the US where government institutions can fail continually and the private sector can still provide the necessities. It is virtually guaranteed that once the vital national interests of the space race were realized by the Apollo Program, that NASA would degenerate into a far worse failure mode than the Soviet Union's space program. We are just now starting to enter the age of private launch services as a result.

    To, in this context of communist domination of space launch services, point to the failure of space programs to develop the economic potential of space is tendentious to say the least. How many people had flown at the time the Kelly Act privatized air mail?

    The math has been done and it is clear:

    Habitats fabricated in free space can provide thousands of times more habitable surface area than Earth.

    The only question is whether technological civilization should leave Earth to ecological remediation.

  • trick question (Score:1, Interesting)

    by Anonymous Coward on Tuesday October 18, 2011 @08:07PM (#37756832)

    The survey question is designed to trick students into answering incorrectly by including a spurious date 1980 after asking the question in brackets. That way the professor can consider himself superior to students when they get it wrong. The guy who says it is impossible has run out of ideas. Based on that alone his opinion should be ignored.

  • by perpenso ( 1613749 ) on Tuesday October 18, 2011 @08:24PM (#37756990)

    The rest of the quote was hilarious though

    20% thought we had been farther than the Moon. Some were indignant on learning the truth: “What do we use the space shuttle for, if not to go to the Moon?!” I can only guess that some students imagined the International Space Station as a remote outpost, certainly beyond the Moon, and likely strategically located next to a wormhole.

    20% of physics students, at this university level, thought that humanity had traveled beyond the Moon? And some thought that we routinely use the shuttle to travel to the moon...

    Well humanity has traveled "beyond" the moon, thats what happens as your orbit and pass over the far/dark side. Perhaps the physics students were being literal, X km above the lunar surface is X km "beyond" the moon for X > 0. :-)

  • by chrb ( 1083577 ) on Tuesday October 18, 2011 @08:33PM (#37757044)

    If expansion of a species into deep space is so easy, and the Drake equation valid, then where is everyone? Where are all of the alien species that should be visiting our planet? Why hasn't the first deep-space faring species colonised the entire universe? I mean, as soon as humans built boats, we spread out across the world and colonised every habitable continent and scrap of land. Why hasn't the same thing happened on an intergalactic level? The possibilities I see are:

    1. We are the first intelligent species to evolve. Highly unlikely but possible.

    2. Expansion of a species into deep space is not feasible in terms of energy and other resources. Every intelligent species that has evolved to this point has hit this constraint.

    3. The Prime Directive. Seems unlikely - we can't get global agreement on borders and border controls, and yet alien governments manage to stop every single one of their citizens from visiting Earth? There are no rebellious alien youths? No Mathias Rusts? [wikipedia.org]

  • (from the original article)

    But I’ll just point out that the idea that we are no longer able to accomplish feats we once could do (like travel to the Moon) clashes with the prevailing narrative that we march forever forward. Not only can’t we get to the Moon at present, but the U.S. no longer has a space shuttle program—originally envisioned to make space travel as routine as air travel. And for that matter, I no longer have the option to purchase a ticket to fly trans-Atlantic at supersonic speeds on the Concorde. Narratives can break. I’ll leave it at that.

    I agree that the ability to move out into the solar system has been sidetracked. It has been a bit of a problem and mankind has pulled back from what we could be doing in terms of getting things done in space. The apparent retrenchment in the ability to travel into space isn't really accurate in the least and this guy really misses what is going on.

    The Apollo missions were a highly focused goal that really pushed the limits of the technology available at the time, perhaps even pushing that technology to its breaking point as the Apollo 13 missions demonstrated very clearly. At best those could be compared to weekend camping trips. We learned a whole bunch about how to live and work in space on those trips that we also learned how tough it would be to go.

    That said, the problem here is that we have been depending on "the government" to get us into space on Manhattan Project type "big science" expeditions, where those programs could be cut and abused because of political whims, graft, and corruption. All of that has happened and more with NASA. Had the NASA budget kept pace with the federal budget from the mid-1960's to today, there most certainly would be at least an outpost on the Moon or elsewhere in the Solar System like the Amundsen-Scott Base at the South Pole. One of the first missions of the "Apollo Applications Program" that was cut was a manned mission to Venus [wikipedia.org]. A mission to Mars has been talked about since the Nixon administration. Getting "out there" has been in the cards, but the funding to make it happen hasn't been there primarily because the political will that got the Apollo program going ran out of steam.

    Private spaceflight efforts, in other words private citizens trying to get into space on their own dime without subsidies from a government entity, has taken a long time to get going. There are established markets for commercial enterprises in space today, primarily concentrated at the moment in the form of telecommunications (including "satellite" television, mobile telephones, and other long-distance communication), navigation (GPS, GLONASS, Galileo, Compass, and others), remote sensing, cartography (Google Maps and others), and reconnaissance (both government and civilian). Add to that list is rapid point-to-point delivery and space tourism that is just beginning to open up. All of these are proven money-makers for those groups who wish to get involved with them and have also made life today much better because they exist as well.

    Far from "we are never going to get into space", we are already there. We are just getting our toes out into the water, so to say, but the commercial development of space-based resources has steadily improved and now represents a multi-billion dollar industry. One of the hang-ups about getting more happening in space has been the cost of spaceflight. In other words, trying to find cheaper ways of getting stuff into space. When a 1 liter bottle of water costs $100,000 or more to send it into space, the economics of getting people into space for settlement simply don't work.

    The fallacy in this article is the presumption that we simply can't get cheaper than $100,000/kg for putting stuff into space and that the cost of going into space is only going to go up. The reason that is currently the case is because the government, a

  • by Daniel_Staal ( 609844 ) <DStaal@usa.net> on Tuesday October 18, 2011 @09:11PM (#37757312)

    The Drake equation has several unknown variables, and even if getting into space is easy, that doesn't mean you'd want to visit Earth. In fact, if you can build habitats to live in deep space (necessary to travel interstellar distances), visiting Earthlike planets is a low-value proposition: It'll take a lot of energy to get here, a lot more to land, a heck of a lot more to take off again, and more yet to leave. Versus staying in the Oort cloud, for instance, where you are likely to be able to find any material you'd be able to find on Earth, and get to it a lot easier. (If possibly in less concentrated chunks.) You'll also avoid any possibly-hostile natives. Only downside is the loss of solar energy, but if you are colonizing deep space anyway you aren't relying on that.

    But back to the Drake equation: f(l) and f(i) are still complete unknowns. (Not to mention f(c) and L, the latter of which we don't even have one measurement of, although ours are already tapering off, so a 50 to 100 years might not be a bad estimate.) There's some indications that f(l) is probably moderately high, but I wouldn't be surprised if f(i) is under one thousandth of a percent. Intelligence is a great survival strategy - once you hit a certain level. Below that level, there's a wide gap where it doesn't appear to help all that much. Exactly why and how humans crossed that gap is an open question. It's quite possible that the universe is teaming with life - and not very much of it is intelligent as we define the term. Or that most of it is too advanced to leak emissions wastefully.

    (And you can probably modify your possibility #1 to be 'Only current intelligent species within a few hundred light years.' Beyond that we'd be unlikely to be able to detect an intelligent species unless it was explicitly trying to contact us.)

  • by 0xdeadbeef ( 28836 ) on Tuesday October 18, 2011 @09:31PM (#37757456) Homepage Journal

    I saw practically no math in your link. I did see a lot of bullshit hand-waving, though.

    I was going to recommend that you read Entering Space [amazon.com] by Robert Zubrin for education in what you believe is cheap and easy, but then I noticed your link had already done so. I liked the part where he dismissed the cost (and Zubrin's estimates) by already assuming a permanent lunar presence with a mass driver putting ore into earth orbit.

  • by garyebickford ( 222422 ) <gar37bic@IIIgmail.com minus threevowels> on Wednesday October 19, 2011 @12:11AM (#37758464)

    Sure they can. At some impressive energy cost (remember the gravity well, it sucks pretty hard). It would be much easier to make floating / submerged habitats than ones in outer space.

    The problem with floating habitats is that the ocean is a very tough place - it's amazingly corrosive (I've been refitting an ocean cruising sailboat and learning more about metallurgy and materials science than I ever imagined), it has currents that will take you where you don't want to go, it's got an equally amazingly adaptable biology that really, really wants to either eat
    or live on whatever is immersed in it, it's constantly expressing the effects of storms both near and 1000s of miles away.

    Almost nothing humans build survives very long in the ocean - a 20 year old boat is almost always OLD. By contrast, as we have seen, most of the entropic forces in space are much more limited, much more constant and predictable - and therefore _mostly_ can be dealt with one way or another. Look at Voyager - still operating after decades.

    So I think that floating habitats will happen - I've been toying with an SF story about one based in one of the gyres - but they will require actually more money than space habitats, because to survive the rigors and variance of the oceans they will have to be _BIG_ and will have to incorporate a range of complex dynamic systems to keep afloat and alive. And I don't know if they will ever be self-sufficient in the way space habitats will have to be.

    In some sense the modern cruise ships are a small non-self-sufficient version. There are a few people who have moved onto cruise ships and live on them all year around, and a Swedish group has proposed a huge version that would be a condo city of 50,000 people [wikipedia.org] that would never come to port (it would be too big), but be tended by a range of smaller vehicles. But the problem remains - at present every floating vessel has to come in to port to have the hull cleaned and repainted every few years, and the corrosion and other effects mean that few commercial vessels last over 20 years - it's cheaper to buy a new one than to fix the old one.

    And besides - ships won't get us off this big 'ship' that we are presently restricted to. In the long term, we really need to 'move on up' and end our dependence on this single point of failure - and bring the rest of our biome with us.

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