The first Science Vision book
at lastMoon base ebook! fly me to the Moon and back, landing on the Moon, what does a moon base look like?
What time is it on the Moon?
Many visionaries have designed and are still designing Moon projects, such as Moon bases, settlements, ways of moon landing and space stations around Earth, but in many such conceptual studies of space and Moon colonies, the basics of physics, engineering and specific conditions are not fully considered, or at all, often in ignorance, or with a wishful "no problem" attitude.
See for example this artist presentation of a huge torus shaped rotating space colony. In the 1970's, Princeton physicist Gerard O'Neill, with the help of NASA Ames Research Center and Stanford University, "showed" that we can build giant orbiting space stations and live in them.
http://www.nas.nasa.gov/About/Education/SpaceSettlement/index.html
In my view, only the artist showed this in his/hers presentation. Surely, nobody ever calculated on what forces would be at work in such a giant rotating structure? I haven't either, but by intuition as an engineer, I say this cannot be done. Just imagine that a steel cylinder at say 500 meter in diameter (the assumed torus cross-section) at 1 bar overpressure would need a wall thickness of around 10 inches (250 mm) solid steel, just to hold against air pressure against vacuum alone and without any safety factors included (then it would become thicker) - all around glass panels?
Even if we assume a lighter construction of a multi-layered hull with stiffening frameworks in between, when we bring the rotational forces of the masses of the hull and its interior structures as shown into account, I don't need to calculate any further - this is fiction only! Moreover, also on Earth we could not construct column-shaped buildings of several kilometers high - they would collapse under their own weight (this is why the steel structure of the Eiffel tower in Paris has its funnel shape - steel has far less compressive strength than concrete and bricks and is four times more heavy).
Besides, we are talking here about tenths of millions of tons of materials that have to be brought into one location and assembled there - how many centuries do we want to spend on building this? Long before such a structure ever would be ready for use, its objectives likely would have become obsolete by economical developments during the time (like f.ex. factories and habitats on the Moon being more profitable) - you can't plan economy on such long terms, nobody would invest!
Ever heard of space-elevators? NASA seems to believe in it and possibly wants to build one, see here:
http://usgovinfo.about.com/library/weekly/aa041702a.htm
"According to NASA, a space elevator would essentially be a long cable with one end attached to a point on the Earth's equator, while the other end remains held by its own outward centripetal force some 22,187 miles (35,787-kilometers) directly overhead in a geostationary orbit. Magnetically powered vehicles would climb the cable, serving as a mass transportation system for moving people, satellites and other payloads between the Earth and space."
Sorry, I'm getting really frustrated here. First of all, the end of this cable is in geostationary orbit, which means it's WEIGHTLESS only there. Below this endpoint in geostationary orbit, this cable actually gets weight, because each lower point of it would have a lower speed than the orbital one for weightlessness. Hence, any space-elevator structure, whether it's a cable, a tube, or whatever, will have to stand on its own feet on Earth, carrying its own weight (unless its mass center is in geostationary orbit, not just the top). See some basic calculations here.
A tube extending 36,000 km out in space, actually is in mechanical rotation (only the outer top is weightless) and so there is a resulting outward centripetal force, together with reduced gravity, giving it a weight of appr. 5% of its mass on Earth surface. This sounds a little, but mind that a steel cable of just one inch diameter and a length of 36,000 km (it almost fits around the Earth's equator), would have a mass of 146,000 metric tons and thus, standing up radially out from Earth, would have a weight on the ground equal to that of around 7000 tons (it can only carry around 25 tons) - compare with the elevator structure shown here - pure fiction!
A simple calculation for steel shows, that any straight column, whether tube, pipe or solid, that is higher than around 6 km, would be near collapse under its own weight (calculated on 500 N/mm2 stress - which is double of what one would allow in practice)! Oh yes, NASA pins its hopes on a newly developed "carbon nanotube" material, shown in tests to be over 100 times stronger than steel. Great, then we can build a column of 600 km high - we are at least in space then! There, a space hotel could be built on the top, where gravity still is around 80% from ground level - don't try to step out for making a "space-walk" (unless you want to meet with your Creator)!
Last but not least. If a load of say 10 tons would "climb" the cable at a speed of around 400 m/s (double the speed of a regular airliner), in order to reach the top in 24 hours, it will get a lateral acceleration (perpendicular to the cable) and If the cable would be a stiff tube of an ideal material with infinite strength, the inertia of this lateral acceleration would yield a momentum (leverage) of well over 10 million ton meter at the tube's foot - it would get ripped off its foundation! In practice of course, any space-elevator would be of a flexible material and thus it will bend under the lateral aceleration forces of the climbers, something totally ignored in this Edward report here: http://www.isr.us/Downloads/niac_pdf/chapter1.html
In that report the height of the space-elevator is about twice that of geostationary orbit, so it indeed is slung out from Earth, not standing on its surface. That would be the only feasible way, but nevertheless, the lateral acceleration forces of the climbers, the latter assumed to have large payloads of many tons, would destroy this "feasible" elevator design, already during the construction of it. As usual, the wish is the father of the thought.
However, NASA can't be that 'stupid', the prove of which I found on this page:
http://www.space.com/071115-moonhab-update-antarctic.html
with title:"Inflatable Moon Base Prototype Heads to South Pole." There it says :" An inflatable habitat designed for explorers on the moon or Mars is headed for an Antarctic test run, NASA said Wednesday." and further:" Working in bulky cold weather gear will also make the deployment more analogous to the challenges facing astronauts clad in cumbersome spacesuits on the moon."
This clearly shows that NASA appeals to the general public's perception that space is cold, which it isn't. Only matter can and always has a temperature and thus the vacuum, empty space, has not, cannot have. Surely the Moon's surface, the ground there, has a temperature, but the vacuum above it has not. This unlike the South Pole, where the air above the ground indeed is very cold. The thermal and also mechanical behavior of spacesuits and habitats in a cold air environment under Earth's atmospheric pressure, is fundamentally and totally different from that in the vacuum environment of the Moon (more similar to the very cold atmosphere of Titan - one of Saturn's moons).
The only feasible way to test a space habitat and living conditions in it, is to bring it in space, into Earth orbit, as Bigelow Aerospace does correctly. Then look at the design of this habitat, a 'militairy hospital tent' in camouflage color. On the Moon you need a white colored and/or shiny polished cylindrical structure, standing on feet. Of course NASA knows all this and thus it is deliberately trying to keep us 'dumb'. NASA lives on the ignorance ('dreams') of the general public. Read more about the physical backgrounds of vacuum conditions in my e-book.
Since the Apollo moon landings, we know quite a bit more about the conditions of the Moon's surface, but the artist-designers do not take these into account and are still in the science fiction phase, or rather, fiction only. Even on credible information sites, such as the BBC, you can find statements like these:
" The Moon has everything needed to sustain life. To build the first Moon base we need take nothing with us. It's all there: aluminum, iron, hydrogen, helium and oxygen." http://news.bbc.co.uk/1/hi/special_report/1999/07/99/the_moon_landing/395447.st
If it now not had said "the FIRST Moon base", I would have agreed, but it will definitely not be the first one that doesn't need to take anything with it - it will basically have to take everything with it. All those nice materials that are on the Moon, do not lie readily available around, but are contained in strong chemical bonds of various kinds, that need quite some equipment and most of all, much energy to collect them and to make them free for use in large quantities, plus a Moon based industry, to make useful products of those materials. To do all that in a vacuum environment, is not precisely the easiest thing to do - read about the conditions in chapter 1 below, where I also describe a possible energy system, based on the use of rigolith (Moon dust).
latest revision : June 18, 2007  |
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As the engineer in electrics, mechanics and energy conversion systems that I am, I make a more realistic analysis of what is possible and develop a program that can lead to establish the first bases and settlements on the Moon, showing designs of such structures and transport systems, with all the functions needed to live there and as can be done with today's technology. This is neither Science yet, nor is it Science Fiction. This is Science Vision instead, the vision of what is, or may be possible within known laws of physics and today's technology, but is yet to be done. | |||||||||||||||||||
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