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Today is the 47th anniversary of the first spaceflight by Yuri Gagarin in Vostok 1.
There are approximately six billion people on Earth, and exactly six people off it.
Has the Space Age really begun yet?
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On 2 April, NASA's European Representative Dr Bill Barry gave the L. J. Carter memorial lecture at the British Interplanetary Society, on the subject of NASA's plans for the future.
There were no surprises. But one or two points that he made bear repeating:
* The objective of the new policy, based on the Bush Vision for Space Exploration, is to generally expand America's capacity for manned operations in space beyond LEO. Sending astronauts to the Moon and Mars are not the essence of the policy, but only examples of ways in which it will be implemented. So the lunar exploration now being prepared is "not a destination-driven project".
* The rockets and spacecraft now being developed under the overall name of Constellation -- specifically: Ares, Orion and Altair -- are supposed to be flexible and affordable. They are also required by Congress to be based on existing systems, hence the emphasis on using the hardware heritage from the Shuttle and Apollo.
* The phrase "Apollo on steroids" was coined by Michael Griffin. He quickly wished that he'd never used it. Constellation will be "amazingly bigger and more capable".
* The first launch of Ares 1 is scheduled for April 2009 (though the Orion spacecraft will not yet be ready then). This shows how much momentum already exists in the Constellation programme -- or, in the words of the soundtrack to the NASA video Dr Barry showed: "The journey has begun."
* The lunar outpost, currently expected to be sited on the rim of Shackleton crater near the lunar south pole, will allow "development and maturation of ISRU". However, specific examples of local resource use were not discussed.
So much for Bill Barry's talk. But what about those NASA plans? Do they really amount to anything more than Apollo on steroids?
I have problems with Constellation.
The plans talk about economic growth and use of the resources found in space -- of which I emphatically approve. One of the six "themes" which guide the architecture is: "Economic expansion: conduct lunar activities with direct benefits to life on the home planet."
Now consider the design of the lunar module, the Altair. It will be a two-stage spacecraft, just like the Apollo LM. As I pointed out to Dr Barry, this means that if the ascent stage tries to make a second lunar landing, it will have no legs to land on. But if the lunar module is used only once, then there will be no significant advantage to developing lunar oxygen for lunar surface refuelling. As Donald Rapp has pointed out (see next item below), if you are producing lunar oxygen, you should use if for all the rocket oxidiser needs between lunar orbit and the surface: descent as well as ascent.
Another point -- a more fundamental one. Once a lunar infrastructure has been set up, who will use it? Clearly, three main users can be identified: government science, lunar tourism, and space-based solar power companies supplying energy to Earth. Which of those have the largest growth prospects? Clearly: tourism and solar power, because they represent mass markets "with direct benefits to life on the home planet". So why do we hear nothing at all about how Constellation will be developed to serve these groups of users?
And why is the focus on the Moon when this is "not a destination-driven project"? To me, this sounds like a way of saying that if the Moon landings fall through because of lack of support by Congress, but there is at least one Constellation launch every now and then, NASA can still claim success for the programme. In reality, of course, the programme is very much driven by the desire to send astronauts to the specific destinations of the Moon and Mars.
In my opinion, NASA is basically repeating and extending Apollo, because they've been ordered by Congress to do so, because Congress has been advised that repeating and extending Apollo is the only game in town, because it was NASA that advised them.
But there is so much more that needs to be done, in which the NASA-led Moon/Mars programme is clearly going to be of marginal value.
There seems to be some confusion about how an early lunar refuelling system might operate -- see Donald Rapp in The Space Review ("The problems with lunar ISRU", September 2006; Dr Rapp is a former Mars researcher at JPL). He writes that NASA's current ideas about using lunar oxygen envisage using it only for lunar ascent propulsion, achieving an almost negligible mass saving at enormous expense -- and that at the same time the ascent propellants have now been changed to nitrogen tetroxide and methyl hydrazine, as in Apollo, rendering oxygen effectively useless even for that purpose.
Dr Rapp also believes that ISRU has to be used right from the outset, not added on later as an "afterthought", and that therefore all the machinery involved in processing lunar regolith has to work robotically right from the start without any human maintenance.
No. The way a lunar oxygen refuelling scheme should be designed is this.
You design a one-stage lunar lander which, without lunar surface refuelling, can be used, Apollo-style, for one descent and one ascent, and this is what you use for initial missions. But at the same time the design allows improvement to a mark II lander which does refuel with oxygen on the Moon, and this is capable of descending to the surface a second time.
While at first it may make only two landings, as experience is gained later versions are certified for progressively more round trips between the surface and orbit, until you end up with a situation in which each lunar lander is in active service for a number of years, making, say, one round trip between the surface and orbit per month, and finally being decommissioned on the surface and broken up for scrap.
Fuel for the lander is brought out from Earth, and transferred to it in low lunar orbit. But the bulk of its propellant demand (80% for methane/oxygen) is supplied on the lunar surface. Thus the lander never has completely full tanks of methane and oxygen simultaneously. Further, each time it takes off from the Moon, it carries enough fuel for a complete round trip back to the surface -- this is obvious as an essential safety measure.
Here is a summary of what I said at my British Interplanetary Society presentation "Building Selenopolis" on 5 March 2008.
I had an audience of about 25 people, who seemed satisfied by my talk, if not wildly enthusiastic. Of course 90 minutes is a long time to listen to one person's voice, even though I had some nice pictures to show them.
I gave each person a summary sheet to take away, listing the key points. The following is an expanded version of that summary, which should give you a good idea of what it was all about.
* NASA Deputy Administrator Hans Mark, 1983, predicted a permanent population of 1000 people living on the Moon by the year 2040, drawing an analogy with Antarctica.
* Von Braun, 1973, had told Mark that the space station will be the enabling technology that allows regular access to the Moon. It will act as a refuelling terminal, following the early designs of Willy Ley (ca. 1945) and Guido von Pirquet (1928).
* The lunar city "Selenopolis" is conceived of as -- following Hans Mark -- a lunar colony of 1000 residents (plus whatever short-stay visitors such a colony might attract). Starting with NASA's planned Moon base in 2022, with a population of 4, our concept of Selenopolis can be reached after 30 years of continuous growth in population and supporting infrastructure, if the growth rate is 20% per annum.
* The current American manned lunar strategy, Constellation (=Orion-Ares-Altair), copies the architecture of Apollo-Saturn. It does not use any space station as a refuelling terminal. Its high cost of operation and lack of versatility for any use other than government science and technology research make it intrinsically resistant to growth. It seems unlikely that Constellation can support 20% growth over 30 years, and we therefore need to question its basic assumptions.
* A growing volume of traffic prompts the evolution of a linear architecture, which connects only two points, into a two-dimensional network, with many branches. A network is the type of transport infrastructure which we use on Earth, in which a number of services cycle between permanent nodes (bus/train stations, airports, seaports).
* Space tourism offers better prospects of generating a large volume of space passenger traffic than does government space science. Virgin Galactic has already signed up almost 200 passengers for its spaceflights, even though they will be only the briefest of suborbital hops. There is a public hunger to fly.
* A single institution such as government will only create a pillar architecture, but a large-scale economic system naturally forms a pyramid. The pillar is basically: one space station, one Moon base (with or more likely without the space station), one Mars base (with or more likely without the space station and the Moon base). The pyramid by contrast builds up a number of space stations before its first Moon base, then builds up more space stations and more Moon bases before its first Mars base, so at that point you might have 10 people on Mars, 1000 on the Moon and 10,000 in low Earth orbit. Consider the Antarctic analogy: when the first Antarctic bases were founded in the 1950s, they could call upon a vast global transport infrastructure.
* The radiation threat from solar storms creates a fundamental design problem for lunar passenger transport. Its solution is an architecture based on Earth-Moon cycler stations. Once the massive radiation shielding has been placed into an Earth-Moon transfer orbit, it can stay there indefinitely.
* The need for rocket propellants in space is another fundamental design problem. Its long-term solution requires the mining of water from near-Earth asteroids. This part of the argument rests on the well-known work of Professor John S. Lewis of the University of Arizona.
* A 40-year asteroid mining scenario is sketched, during which a cumulative total of 50,000 tonnes of water is delivered to Earth orbit for sale. (This is my own attempt to reproduce Lewis's reasoning, adapted to my own purposes.)
* Asteroidal water has two important large-scale uses in orbit: for making rocket propellants, and in its raw state as radiation shielding, thus increasing its attractiveness. It can be marketed to government science programmes, commercial microgravity research and manufacturing projects, space tourism companies and space-based solar power companies.
* By around 2050, a lunar colony of 1000 residents -- Selenopolis -- will be possible if it represents only a small fraction of total manned space activity by that time. But if it is conceived as a one-off project in splendid isolation from any supporting space economy, its continuing reliance upon public funding will make it unlikely that it will survive for long, even if it is started.
* We are therefore no longer talking about flying a mission to the Moon, but about stimulating a growth-oriented economic system. The impetus to create this system is coming and presumably will continue to come from entrepreneurs, not from the established space agencies.
* Economic access to Mars -- building Areopolis -- requires the same basic principles: permanent cycler spacecraft, asteroidal water mining, and the prior growth of a large supporting space infrastructure. Most of the mass of our Earth-Mars transport system -- rocket propellants, radiation shielding and water for life-support systems -- is already in interplanetary space, in orbits very similar to those we need.
* Systematic industrial use of the near-Earth asteroids opens up the possibilities of large-scale space construction using the resources of the main belt, which are 10,000 times greater. This mass of material, combined with the almost inexhaustible flux of solar power, offers the material basis for a 21st-century space industrial revolution analogous to the 18th-century one, with analogous transforming possibilities for the whole of human society.
The winners of the Arthurs in 2008 were announced at the UK Space Conference on 29 March. The evening began with a tribute to Sir Arthur from special effects wizard Mat Irvine. This was followed by some words from Peter Marshall of the Arthur C. Clarke Foundation, and the tributes were rounded off by a video message from Sir Patrick Moore.
The winners are:
Best Corporate/Team Achievement -- The Mars Express Team
Best Individual Achievement -- Ian Taylor MP
Best Student Achievement -- Alison Gibbings
Best TV/Radio Presentation -- "Britain's Space Race" by Martin Redfern and Heather Couper
Best Written Presentation -- "Jane's Spaceflight Directory" by David Baker
Best Film Presentation -- "In The Shadow Of The Moon"
Achievement in Education -- The Faulkes Telescope Project -- Director: Paul Roche
Best Space Reporting -- Spaceflight magazine: Editor, Clive Simpson
Inspiration Award -- Piers Sellars
Outreach Award for the Public Promotion of Space -- Maggie Aderin
Space Entrepreneur -- Alan Bond
Lifetime Achievement Award -- Sir Martin Sweeting
The George Abbey Award -- The Reliant Robin Team -- "the team whose space achievement made us laugh the most"
More details on the awards website.
The press release can be found here.
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