NOTE: I am not a NASA employee. I do not speak for NASA or anyone else. None of these answers represent NASAÕs position, or my employerÕs position, or the position of any organization IÕm familiar with.
Most of this solar system is rock and radiation. ItÕs time to change
that. We can bring the vast reaches of space to life, and gather immense wealth
in the process. What, exactly, are we waiting for?
In the 1970Õs, the physicist Gerard OÕNeill with the help of NASA and Stanford University showed that it was possible to build giant orbiting spaceships and live in them. Are these projects still exist today for the NASA?
No. NASA is focused on
exploration, not colonization. There is one, very small educational project
concerned with colonization. Every
year NASA Ames Research Center invites 6-12th grade students from around the
world to design space settlements they would like to live in. These designs are judged by NASA
engineers and scientists. The best receive awards and an invitation to visit
NASA Ames. See http://lifesci3.arc.nasa.gov/SpaceSettlement/
for details.
Which would be the advantage and the disadvantages of the life in these space colonies in orbit?
Advantages: wealth, power, growth, survival -- and 0g recreation
(there are also great views).
Wealth, power, and growth come from access to the resources of the whole solar system, rather than just Earth. For example, one small asteroid (3554 Amun) has $20 trillion dollars worth of metals. Solar power satellites can supply all the power we need with no greenhouse gasses (or any other emissions), no mining, and no drilling. The materials from the single largest asteroid can build space colonies with living areas totalling more than 150 times the surface area of the Earth.
If we do not colonize space, someday civilization will be destroyed. If nothing else happens, sooner or later a large asteroid will hit us. This has happened many times in the past (it killed the dinosaurs) and will happen again. Space colonies can help in two ways: 1. If Earth is seriously damaged, colonies can help us recover, just as people hurt by the tsunami were helped by unaffected countries. 2. Space colonies need materials to grow. They will have an interest in keeping watch for asteroids and comets that would otherwise strike Earth. When one is found, space colonists can tear it apart and use the materials to build more colonies, eliminating the problem and building valuable real estate at the same time.
0g recreation is just plain fun.
Take a look at videos of astronauts playing in 0g at
http://www.nas.nasa.gov/About/Education/SpaceSettlement/Video/. ItÕs a blast.
Imagine if you had a lot more room and years to get good at it. For
example, weightless soccer will be amazing. You launch yourself at the ball and
the whole game is played in 3D, not on a flat surface like on Earth. Dance will
literally go to new heights.
Anyone can jump higher than Baryshnikov, and weightless and low-g
dancers will doubtless take advantage of this new freedom of movement. Of
course, many will only ask for some privacy and the right company. Honeymoon hotels will be a major
attraction for orbital tourists, and space colonists will have access to them
at all times.
The view of Earth from space is one of the most beautiful in the galaxy.
Everyone who has seen it has been deeply touched. We should all get that
chance. Early space colonists will have it every day.
Disadvantages: Particularly at first, each colony will be fairly
small Š perhaps a few kilometers across with 5-10,000 people. Only later will colonies the size of a
city become practical. Of course,
travel to other colonies and Earth should be fairly easy.
The construction of these space colonies brings
several important questions : which would be the processes of possible
construction? With
which materials? Which energy? And which protections against the solar radiations ?
The Moon and Near Earth Asteroids (NEAs) have
all the materials we need.
The Moon has ample supplies of metals,
silicon, and oxygen. These are
available in large quantities in the surface dust, called regolith. Regolith
covers the Moon to a depth of at least several meters, and probably much
deeper. Unfortunately, the Moon
lacks carbon, nitrogen, and has hydrogen for water only at the poles.
Fortunately, some NEAs are actually easier to
get to than the Moon, meaning it takes less rocket fuel for a round trip. Asteroids are a much richer source of
materials than the Moon. There is ample carbon and water, as well as plenty of
metals and other useful materials.
In orbit, solar energy is plentiful and
reliable. Unlike Earth, where
night and clouds dim the sun frequently, in space the sunÕs energy is
constantly available in all orbits except those very close to Earth. While low orbits are often in shadow,
high orbits experience eclipse only a few minutes a year, and these are
completely predictable. This is why most satellites use solar power. Plans for
multi-megawatt solar power satellites have been developed to supply power to
Earth. The same ideas and technology will be available for space colonies.
Radiation protection requires about 10
tons of material per square meter of surface area. This is sufficient to reduce
radiation to acceptable levels. Almost any material will do. Lunar dust and/or asteroid materials
left over from processing are good candidates.
Molecular nanotechnology seems to be a major improvement in manufacturing technology which will facilitate the construction of the space station. Why?
Advanced molecular nanotechnology can make things far lighter and more
capable than is possible today. In
particular, very advanced molecular nanotechnology should be able to make
launch vehicles hundreds of times more efficient than todayÕs shuttle. This
would radically reduce the cost of space colonization, making it practical much
more quickly than otherwise.
If itÕs possible to build orbital space station, can we also talk about the colonization of the Moon or the planet Mars?
For colonization, the Moon and Mars are far inferior to orbit, at least
at first. The biggest problem is
gravity. The Moon has 1/6g and
Mars 1/3g. We have no idea what
will happen to children who grow up in reduced gravity, with one exception:
they will be too weak to visit Earth. On Earth they will weigh 3-6 times what
their bones and muscles are accustomed to. At best, they will be wheelchair
bound. At worst, they will be
bed-bound or die of heart failure.
Never visiting Earth may be acceptable in a couple hundred years, but
not for the first few colonies.
How many parents will accept that their children can never visit their
homeland, never attend the great universities of Earth, and never enjoy EarthÕs
beauty and culture first hand?
Orbital colonies can be rotated to produce pseudo-gravity at any desired
level, including 1g. If a child of
an orbital colony gets a full scholarship to Harvard, they can go. If they are an Olympic class athlete,
they can compete on Earth. If they
are a world-class musician, they can tour the great concert halls of our native
planet.
In addition, orbital colonies have continuous ample reliable solar
energy, terrific views of Earth, weightless recreation, simplified 0g
construction, much greater growth potential, and far easier access to Earth
during early construction and to market their trade good.
Mankind will colonize orbital space first. Eventually, long after the first wave of colonization, it
may make sense to live on the Moon or Mars.
Whether it acts of Mars or an orbiting station, these projects will be very expensive. How to find the financings, knowing that they will probably not be refunded before long years?
There are two ways to fund space colonization:
1.
Decide that weÕd rather colonize space than kill each other. The U.S.
alone spends over half a trillion dollars per year on defense. This buys a
global military empire that could not protect us from nineteen guys with box
cutters. Half the US defense
budget would easily pay for space colonization in a few decades.
2.
Barring a world-wide outbreak of sanity, we can fund colonies one
profitable step at a time. One
possible sequence of steps:
a.
Sub-orbital tourism
b.
Orbital tourism (especially 0g honeymoon hotels)
c.
Low-g old age homes (no wheelchairs necessary)
d.
Lunar mines for solar power satellites (multi-trillion dollar market)
e.
Asteroid mines for mineral resources (ditto)
f.
Orbital colonies
Transportation from Earth to orbit costs about $20,000 per kg and a few percent of all launches end in a large explosion. This must be fixed. In all of the space age there have only been a few thousand launches. If there had only been a few thousand airplane flights, if only a few thousand cars had been made, if only a few thousand train trips had ever taken place, transportation on Earth would be in a pretty sorry state. We need a lot of launches to get good at it. Tens of thousands. Millions. Launching communication, military, and science satellites will never get us there. The only market big enough is tourism. ThatÕs the ticket to cities in the sky.
Sub-orbital tourism is well on its way. SpaceShipOne, built by Burt RutanÕs team and funded by Paul Allen, can carry three people and has flown into space twice. RutanÕs team is now developing SpaceShipTwo, which is intended to fly paying customers in a few years. The cost is expected to be about $200,000 per flight at first, dropping considerably if there is enough traffic. While that is a great deal of money, many well-off middle class individuals could afford it if they really, really, really wanted to go. Say, bad enough to mortgage the house. A lot of wealthy people could afford it quite easily. If all goes well, flying thousands of tourists into space will give the space industry the experience and profits it needs to develop orbital tourist vehicles.
Orbital tourism has started, but in a very limited way. The Russians have flown two space
tourists to the International Space Station (ISS). Both have had a fantastic
experience. However, the cost is about $20 million. Large-scale orbital tourism
will require much less expensive vehicles. Once available, long periods of weightlessness and literally
out-of-this-world views are expected to draw thousands, maybe hundreds of
thousands, of people into space for the experience of a lifetime.
These tourists will want nice hotels to stay in. Nice hotels require people to keep them
that way. Some of these workers may become the first permanent residents in
space. A few are bound to like it and be clever enough to find a way to stay on
indefinitely. The first space colonists may be maids, bellhops, and musicians!
Once weightless orbital hotels are commonplace, it will occur to some
wealthy people that gravity is a real problem for an aging, weak body. ItÕs
gravity that puts you in a wheelchair.
Low-g and weightless communities for aging billionaires may be the
second wave of permanent residents in space. Eventually, the cost of these
communities will come down enough for EarthÕs growing middle-class to enjoy
them.
As mentioned before, solar power satellites can supply the Earth with
far more energy than we use today without any emissions or mining Š on Earth.
Lunar mines can supply the necessary materials. The Moon has everything we need
to build a nearly unlimited supply of solar power satellites: metals for
structure and silicon for solar cells. Developing solar power satellites and
lunar mines will give us experience building large space structures and
exploiting solar system rock and radiation.
Asteroids contain vast quantities of almost every sort of material; more
than enough to supply Earth and a growing space community for millennia. As we know from the destruction of the
dinosaurs, some asteroids come very close to Earth. These can be mined for
their metals and other resources at a great profit. The experience gained will
provide access to materials the Moon lacks, especially carbon and water; both
essential to life.
At this point we have a robust, inexpensive transportation system moving
people between Earth and orbit developed by tourism, vast quantities of energy
from solar power satellites, and ample supplies of materials from the Moon and
asteroids. We just need to put
them in a pot, simmer lightly, and voila! Š space colonies.
Of course, even with excellent transportation, plentiful energy, and
ample materials, construction of kilometer-scale space colonies will be a
monumental engineering task. One that any engineer worth their salt would love
to take on. And they will.
In 2004, Burt Rutan, a famous aircraft designer, said that orbital tourism will be largely affordable in 25 years. What do you think about this prediction?
If anyone else made this prediction, I would call it bunk. Coming from Burt, maybe.
Burt built SpaceShipOne, the first, and so far only, private vehicle to
take a human into space. Rutan not only put a private manned vehicle into
space, he did it for a few tens of millions of dollars and even made a small
profit. He and Paul Allen, who
financed SpaceShipOne, made ten million dollars for winning the X-Prize, got a
couple million more for painting ŌVirginÕ on the tail, and then made even more
money selling the technology to Richard Branson. This was a remarkable achievement.
I think it is very likely that Rutan will build practical sub-orbital
tourist vehicles, and that this will lead to a profitable business. Orbital flight, however, is much more
difficult. Sub-orbital vehicles
just go straight up, then straight down again, at relatively low speeds. To
stay in orbit, you must go over 25,000 km/hour. Otherwise you fall out of orbit
and either burn up in the atmosphere or crash into the ground. Going that fast
is not only difficult to do, it means that you re-enter the atmosphere at the
same speed. SpaceShipOne re-enters
the atmosphere very slowly, so there is little stress on the vehicle and little
heat build-up. The same techniques
wonÕt work for orbital flight. I
donÕt think Burt has solved the problems of orbital flight and return, but he
is a brilliant engineer and may come up with something that will work. I
certainly hope so.
And, in the future, when can we hope the first operational space colony able to accommodate his first inhabitants?
If we really do get practical orbital tourist vehicles in 25 years, the
most difficult problem (transportation from Earth to orbit) will be solved. A
colony could conceivably be built within a few decades after that. That means that the younger people on
this planet may see space colonies in their lifetime.
There is a way to make it happen faster. Get to work! The rock and radiation is waiting É