Space colonization essay !

Hello there,

I'm a student and I'm in my final year and I wish to do my essay about space colonization.
My first topic is about the planets or planetary bodies that are not suitable for this purpose. Such as planets or planetary bodies outside of our solar system. As I understand it it is simply to far to get within a lifetime, so that sugests we would have to have babies in order to do that. But due to cosmic radiation, this presents a large amount of difficulties. Sperm decrease, damage to egg cells etc.
Even though there are ways to protect ourselves from this radiation, it is not enaugh to allow us to have babies in space. Even if a baby could make it out of the womb we would still have problems protecting it from this cosmic radiation. This and the lack of gravity make it impossible to do so in space. But imagine, if we were able to create an atmosphere on Mars or on any other planet, would THAT allow us to have children? Since the atmosphere should filter a part of this radiation?

Greets!

On a sunny day (Tue, 1 Nov 2011 12:04:00 +0000) it happened TheBeerjunkie
wrote in
:


Hello there,

I'm a student and I'm in my final year and I wish to do my essay about
space colonization.
My first topic is about the planets or planetary bodies that are not
suitable for this purpose. Such as planets or planetary bodies outside
of our solar system. As I understand it it is simply to far to get
within a lifetime, so that sugests we would have to have babies in order
to do that. But due to cosmic radiation, this presents a large amount of
difficulties. Sperm decrease, damage to egg cells etc.
Even though there are ways to protect ourselves from this radiation, it
is not enaugh to allow us to have babies in space. Even if a baby could
make it out of the womb we would still have problems protecting it from
this cosmic radiation. This and the lack of gravity make it impossible
to do so in space. But imagine, if we were able to create an atmosphere
on Mars or on any other planet, would THAT allow us to have children?
Since the atmosphere should filter a part of this radiation?

Greets!

If you can accelerate at a constant 1G,
and halfway turn around and de-accelerate at 1 G,
then most of the problems you state are solved.
That creates artificial gravity, and brings the time it takes to the next star withing a lifetime/
So, focus should be on propulsion, likely nuclear, but with the current state humanity is in
(NASA had already plans for a nuclear engine many many many years ago,
but it was abandoned 'too dangerous', so when ToysRus bought NASA
there was no longer hope for a US colonisation of planets.
Add some stupid concepts about light speed, and here we are, and will possibly stay.
The Chinese just launched a spacecraft to rendezvous with their orbiting space lab.
If things go the way they do now, the the Chinese will be first at mars,
and then it will truly be the red planet.
Later US astronuts, who will likely smash down with airbags, will have to pay landing rights
and will find a choice of the finest Chinese restaurants waiting for them.
Expensive too.

On Nov 1, 8:38*am, Jan Panteltje wrote:
On a sunny day (Tue, 1 Nov 2011 12:04:00 +0000) it happened TheBeerjunkie
wrote in
:











Hello there,

I'm a student and I'm in my final year and I wish to do my essay about
space colonization.
My first topic is about the planets or planetary bodies that are not
suitable for this purpose. Such as planets or planetary bodies outside
of our solar system. As I understand it it is simply to far to get
within a lifetime, so that sugests we would have to have babies in order
to do that. But due to cosmic radiation, this presents a large amount of
difficulties. Sperm decrease, damage to egg cells etc.
Even though there are ways to protect ourselves from this radiation, it
is not enaugh to allow us to have babies in space. Even if a baby could
make it out of the womb we would still have problems protecting it from
this cosmic radiation. This and the lack of gravity make it impossible
to do so in space. But imagine, if we were able to create an atmosphere
on Mars or on any other planet, would THAT allow us to have children?
Since the atmosphere should filter a part of this radiation?

Greets!

If you can accelerate at a constant 1G,
and halfway turn around and de-accelerate at 1 G,
then most of the problems you state are solved.
That creates artificial gravity, and brings the time it takes to the next star withing a lifetime/
So, focus should be on propulsion, likely nuclear, but with the current state humanity is in
(NASA had already plans for a nuclear engine many many many years ago,
but it was abandoned 'too dangerous', so when ToysRus bought NASA
there was no longer hope for a US colonisation of planets.
Add some stupid concepts about light speed, and here we are, and will possibly stay.
The Chinese just launched a spacecraft to rendezvous with their orbiting space lab.
If things go the way they do now, the the Chinese will be first at mars,
and then it will truly be the red planet.
Later US astronuts, who will likely smash down with airbags, will have to pay landing rights
and will find a choice of the finest Chinese restaurants waiting for them..
Expensive too.

We do seem to have a fly-by-rocket lander gap, including the one of
our Apollo era that doesn't seem to work as we've been told. No doubt
those Long March landers will come in real handy, and we can rent them
for a million dollars per hour or per kg of payload (plus the usual
tax, insurance and fuel).

Btw, even 0.1 G worth of constant acceleration/deceleration is going
to make at least those most nearby exoplanets doable. Fusion rockets
such as those offered by William Mook should more than do the trick.

http://translate.google.com/#
Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / “Guth Usenet”

Dear TheBeerjunkie:

On Nov 1, 5:04*am, TheBeerjunkie TheBeerjunkie.
wrote:
Hello there,

I'm a student and I'm in my final year and I wish to do
my essay about space colonization.

My first topic is about the planets or planetary bodies
that are not suitable for this purpose. Such as planets
or planetary bodies outside of our solar system. As I
understand it it is simply to far to get within a lifetime,
so that sugests we would have to have babies in order
to do that. But due to cosmic radiation, this presents
a large amount of difficulties. Sperm decrease, damage
to egg cells etc. Even though there are ways to protect
ourselves from this radiation, it is not enaugh to allow us
to have babies in space. Even if a baby could make it
out of the womb we would still have problems protecting
it from this cosmic radiation.

If we are protected, then so are our babies and our gametes.

This and the lack of gravity make it impossible to do so
in space.

Accelerate an asteroid, and send it on its way towards a destination.
Place a rotating body in its "shadow", the rotation producing
"gravity". There is your protection.

Nature seems to have previously pureed organisms, and sent their DNA
to the stars...
http://en.wikipedia.org/wiki/Panspermia

But imagine, if we were able to create an atmosphere
on Mars or on any other planet, would THAT allow us to
have children? Since the atmosphere should filter a part
of this radiation?

Just build underground, and under glass... on either Mars or the Moon.
http://en.wikipedia.org/wiki/The_Moo...Harsh_Mistress

Better still, wait until the race has matured, and does not feel
compelled to overbreed, transfer its various voluntary mental
illnesses to new populations, and maybe we will figure out FTL drive,
making such precautions unnecessary.

David A. Smith

On a sunny day (Tue, 1 Nov 2011 11:58:54 -0700 (PDT)) it happened Brad Guth
wrote in
:

We do seem to have a fly-by-rocket lander gap, including the one of
our Apollo era that doesn't seem to work as we've been told. No doubt
those Long March landers will come in real handy, and we can rent them
for a million dollars per hour or per kg of payload (plus the usual
tax, insurance and fuel).

Btw, even 0.1 G worth of constant acceleration/deceleration is going
to make at least those most nearby exoplanets doable. Fusion rockets
such as those offered by William Mook should more than do the trick.

http://translate.google.com/#
Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / “Guth Usenet”

I was thinking that if all those flights to the International Space Junk Station
had been used to build a huge nuclear powered interplanetary spacecraft....
then we would not have to burn it up in the atmosphere and endanger humanity
with the debris, but could fly to the planets with a travel time of only weeks.

Jan Panteltje wrote:
On a sunny day (Tue, 1 Nov 2011 11:58:54 -0700 (PDT)) it happened
Brad Guth wrote in
:

We do seem to have a fly-by-rocket lander gap, including the one of
our Apollo era that doesn't seem to work as we've been told. No
doubt those Long March landers will come in real handy, and we can
rent them for a million dollars per hour or per kg of payload (plus
the usual tax, insurance and fuel).

Btw, even 0.1 G worth of constant acceleration/deceleration is going
to make at least those most nearby exoplanets doable. Fusion rockets
such as those offered by William Mook should more than do the trick.

http://translate.google.com/#
Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / “Guth Usenet”

I was thinking that if all those flights to the International Space
Junk Station had been used to build a huge nuclear powered
interplanetary spacecraft.... then we would not have to burn it up in
the atmosphere and endanger humanity with the debris, but could fly
to the planets with a travel time of only weeks.

An Orion type spacecraft (that uses exploding atomic bombs and a pusher
plate) is an idea that has been around for a long time and is technically
feasible, but would you want the treaty on the ban of nuclear devices in
outer space to be annulled?

--
Mike Dworetsky

(Remove pants sp*mbl*ck to reply)

On 01/11/2011 12:04, TheBeerjunkie wrote:
Hello there,

I'm a student and I'm in my final year and I wish to do my essay about
space colonization.
My first topic is about the planets or planetary bodies that are not
suitable for this purpose. Such as planets or planetary bodies outside
of our solar system. As I understand it it is simply to far to get
within a lifetime, so that sugests we would have to have babies in order
to do that. But due to cosmic radiation, this presents a large amount of
difficulties. Sperm decrease, damage to egg cells etc.
Even though there are ways to protect ourselves from this radiation, it
is not enaugh to allow us to have babies in space. Even if a baby could
make it out of the womb we would still have problems protecting it from
this cosmic radiation. This and the lack of gravity make it impossible

The trick for gravity was demonstrated in 2001 a space odyssey. The zone
you want to have effective gravity needs to be on the inner surface of a
rotating cylinder - with or without velcro shoes and flooring. It would
work but might take some getting used to.

to do so in space. But imagine, if we were able to create an atmosphere
on Mars or on any other planet, would THAT allow us to have children?
Since the atmosphere should filter a part of this radiation?

You should look up terraforming. Mars might benefit from the addition of
powerful greenhouse gasses like SF6, CF4 or C2F6 to its atmosphere. All
of these would be gasses for part of the time and stable and heavy
enough to find escaping from the planets weaker gravity difficult.

--
Regards,
Martin Brown

On Nov 2, 3:06*am, Jan Panteltje wrote:
On a sunny day (Tue, 1 Nov 2011 11:58:54 -0700 (PDT)) it happened Brad Guth
wrote in
:

We do seem to have a fly-by-rocket lander gap, including the one of
our Apollo era that doesn't seem to work as we've been told. *No doubt
those Long March landers will come in real handy, and we can rent them
for a million dollars per hour or per kg of payload (plus the usual
tax, insurance and fuel).

Btw, even 0.1 G worth of constant acceleration/deceleration is going
to make at least those most nearby exoplanets doable. *Fusion rockets
such as those offered by William Mook should more than do the trick.

http://translate.google.com/#
Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / “Guth Usenet”

I was thinking that if all those flights to the International Space Junk Station
had been used to build a huge nuclear powered interplanetary spacecraft.....
then we would not have to burn it up in the atmosphere and endanger humanity
with the debris, but could fly to the planets with a travel time of only weeks.

Actually, using lithium-6 and deuteride is even better, at least
according to William Mook.

In the meantime, having a Boeing OASIS at the Earth-moon L1 would have
helped as of decades ago, such as for it inventory of conventional LOx/
LH2 and always HTP plus a good hydrocarbon synfuel, would have at
least made our solar system and especially our moon and Venus
commercially and even privately accessible.

"Lithium-6 deuteride produces alpha particles moving at 33000 km/
sec" / William Mook

However, my Radon alpha Ion thruster with its potential of 150,000 km/
sec might be even better since the necessary Radium that's producing
Radon has such a long half life. There should be lots of Radium in
our moon and especially on Venus.

http://translate.google.com/#
Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / “Guth Usenet”

On a sunny day (Wed, 2 Nov 2011 10:18:13 -0000) it happened "Mike Dworetsky"
wrote in
:

Jan Panteltje wrote:
On a sunny day (Tue, 1 Nov 2011 11:58:54 -0700 (PDT)) it happened
Brad Guth wrote in
:

We do seem to have a fly-by-rocket lander gap, including the one of
our Apollo era that doesn't seem to work as we've been told. No
doubt those Long March landers will come in real handy, and we can
rent them for a million dollars per hour or per kg of payload (plus
the usual tax, insurance and fuel).

Btw, even 0.1 G worth of constant acceleration/deceleration is going
to make at least those most nearby exoplanets doable. Fusion rockets
such as those offered by William Mook should more than do the trick.

http://translate.google.com/#
Brad Guth, Brad_Guth, Brad.Guth, BradGuth, BG / “Guth Usenet”

I was thinking that if all those flights to the International Space
Junk Station had been used to build a huge nuclear powered
interplanetary spacecraft.... then we would not have to burn it up in
the atmosphere and endanger humanity with the debris, but could fly
to the planets with a travel time of only weeks.

An Orion type spacecraft (that uses exploding atomic bombs and a pusher
plate) is an idea that has been around for a long time and is technically
feasible, but would you want the treaty on the ban of nuclear devices in
outer space to be annulled?

You mean the sun is illegal?

On Nov 1, 8:04*am, TheBeerjunkie TheBeerjunkie.
wrote:
Hello there,

I'm a student and I'm in my final year and I wish to do my essay about
space colonization.
My first topic is about the planets or planetary bodies that are not
suitable for this purpose. Such as planets or planetary bodies outside
of our solar system. As I understand it it is simply to far to get
within a lifetime, so that sugests we would have to have babies in order
to do that. But due to cosmic radiation, this presents a large amount of
difficulties. Sperm decrease, damage to egg cells etc.
Even though there are ways to protect ourselves from this radiation, it
is not enaugh to allow us to have babies in space. Even if a baby could
make it out of the womb we would still have problems protecting it from
this cosmic radiation. This and the lack of gravity make it impossible
to do so in space. But imagine, if we were able to create an atmosphere
on Mars or on any other planet, would THAT allow us to have children?
Since the atmosphere should filter a part of this radiation?

Greets!

--
TheBeerjunkie

Well, you're focusing on a lot of inconsequential details and missing
the big picture.

Look first at the trade in goods between nations -

Trade Statistics
http://www.worldshipping.org/about-t...ade-statistics

Ships
http://www.worldshipping.org/about-t...ry/liner-ships

6,000 ships
891 million tons per year
$4.5 trillion per year

The world's economy generates about $70 trillion per year.

If you've ever shipped anything, or spoken with those who work in
shipping you'd know that it takes between 30 and 90 days.

So, each ship cycles say 45 days on average and that means 8 trips per
year. 891 million tons per year and 6,000 ships carrying 8 loads is
an average of about 18,250 tons.

To colonize the solar system this is the level of commerce we need
between worlds.

That is, 6,000 ships carrying 20,000 tons around the inner solar
system.

Do we have such a capability?

Sure! The idea was developed by the same people who brought you the
atom bomb. In fact, the idea of using atomic energy to blast a rocket
across space was first discussed in a letter from the Hungarian
scientist Leó Szilárd to his good friend Jacob Bronowski. How was Leó
Szilárd? He was Einstein's favorite student. The inventor of the
cyclotron and the nuclear reactor (though Fermi later claimed
credit). He wrote the letter to FDR to get the Manhattan project
rolling, which Einstein signed. Most scientists thought an Atom Bomb
was a bad idea. Leó Szilárd convinced them that the bomb would also
make the Atomic Rocket possible, and that would free us from endless
war by turning our talents and irrational desires to compete outward
into the frontier of the great cosmos around us.

http://en.wikipedia.org/wiki/Le%C3%B3_Szil%C3%A1rd

So, its not surprising that out of the atom bomb program came designs
for atomic rockets.

http://en.wikipedia.org/wiki/Project..._propulsion%29

By 1965 Nikolai Voitenko adapted his armor piercing round to
compressing aneutronic materials - lithium-6 deuteride to create
fusion bombs that had zero radiation effects zero pollution.
Lithium-6 deuteride produces alpha particles (helium nuclei) and no
long lasting radiation. Alpha particles have the added benefit that
they are easily deflected.

The Russians promptly classified this, but later, this was released to
the public and in the 1980s was the subject of significant research
and confirmation in the West.

Modern methods of micro-manufacturing (MEMS) can be adapted to make
micro-Voitenko compressors to be used as 'spark plugs' to detonate
larger sticks of Lithium-6 Deuteride.

This propellant costs less than $200 per kilogram and can easily be
extracted from the ocean. The ocean contains 250 billion tons of
lithium. 2.5% of this total 6.25 billion tons is the isotope
lithium-6. About 1 in 6,000 hydrogen atoms in the ocean is the
hydrogen isotope deuterium. Reacting these two isotopes produces
lithium-6 deuteride a powder that when compressed can me made into a
solid massing 0.83 kg per liter.

What kind of rockets can be made with this sort of propellant? Well,
the alpha particles produced by the reaction move at about 11% light
speed. That's 33,000 km/sec. By comparison, the Space Shuttle Main
Engine exhaust speed is 4.3 km/sec.

The Russian mathematician Tsiolkovsky was the first person to write
down an accurate description of rocket operation, with his rocket
equation;

Vf = Ve * LN(1/(1-u))

Which can be rewritten to solve for u

u = 1- 1/EXP(Vf/Ve)

Where u = propellant fraction
Vf = final velocity (the speed you want to achieve)
Ve = exhaust velocity (the exhaust speed of the rocket's
reaction)
EXP=exponential function
LN = natural logarithm function (base e, Euler)

The Space Shuttle achieves an ideal final velocity of 9.2 km/sec when
all the losses are accounted for. This means that the propellant
fraction must be;

u = 1 - 1/EXP(9.2/4.3) = 0.882229 ~88.2%

Which means that the structure and payload can't be more than 11.8%

A fusion powered atomic rocket using lithium-6 deuteride would have a
propellant fraction of;

u = 1 - 1/EXP(9.2/33000) = 0.000278749 ~ 0.028%

Which means that structure and payload are nearly 100% of the
vehicle's mass.

With an atomic rocket, you don't operate at minimum energies - so
called Hohmann transfer orbits - which make interplanetary navigation
very difficult, time consuming and costly.

With a safe reliable atomic rocket, you operate at constant gee. This
varies with distance. The distance from Earth to Moon for example, is
around 400,000 km. That's 400 million meters. You accelerate at 1
gee to the half way point, and then slow at 1 gee until you land on
the moon's surface.

D = 1/2* V^2 / a

Solving for V

(2 * D * a) ^(1/2) = V

Where D = distance of boost, 2e8 m
a = acceleration, 9.82 m/s/s
V = velocity (m/s)


V = 62,673 m/sec = 62.7 km/sec

There are two boosts, one to speed up, one to slow down. A total of
125.4 km/sec.

Dropping this into Tsiolkovsky's equation;

u = 1 - 1/EXP(125.4/33000) = 0.0037927 ~ 0.38%

Again nearly 100%. A round trip would require 0.78% propellant with
no provision to refuel on the moon.

A ship that carried 20,000 tons and was 20% structure - would weigh
4,000 tons empty. It would be the size of a typical container ship
this size. It would carry about 200 tons of lithium-deuteride.

How long would the trip take?

Well Apollo took 4 days to get to the moon along a minimum energy
trajectory.

This ship boosts at 1 gee.

V = a * t

so

t = V/a

V=62,673 m/sec
a=9.82 m/s/s

So, t = 6,382.3 seconds = 1.773 hours per leg. That's 3.546 hours
per trip out. A round trip would take 7.092 hours flight time. With
55 minutes on the moon for unloading and loading - a single ship could
carry 3 cargoes to the moon per day. 1,095 cargoes per year.

21,900,000 tonnes per year.

This is 1/40th the cargo capacity of the Earth's fleet of 6,000 cargo
ships.

Analysis of space colony designs by NASA in the 1970s indicate that
approximately 49 tons of material is required per person to set up a
colony, and to maintain a person on the colony requires 0.1 tons per
year.

So, one ship can support 219 million people on the moon! Once its set
up. The 10,731 million tons of hardware would take one ship 490 years
to build out. It would take 50 ships less than 10 years. 49 tons per
person and 20,000 tons of cargo carrying capacity, means the colony
ships would carry 408 people per flight each. That's 1,224 per day
per ship in operation. 446,760 people per year per ship. Fifty
ships would carry 22.3 million per year. Over 10 years, 219 million
people would be supported.

Each ship uses 600 tons per day of lithium-6 deuteride and produces
600 tons per day of helium exhaust. 50 ships use 30,000 tons per
day. 10.95 million tons per year of lithium deuteride. There are 6
billion tons of lithium-6 in the oceans. So, this is a 600 year
supply. Other planets have lithium, and so a large supply of this
must be found, or a way to use it more economically.

For comparison, ALL the world's industry and transport could be
powered by only 805 tons of lithium deuteride. So, this gives the
scale of what we're talking about. The operation of a single 20,000
ton moonship of the type we've described here, would use energy at
nearly the rate we use it on Earth today for everything else!!

Of course, building even a small outpost with a single ship -
increasing the base in size by 400,000 people per year - would have a
huge impact on the human race.

If we can do that - many would ask - why can't we do something on
Earth to make life better for everyone?

People would take seriously large infrastructure projects like these;

http://www.schillerinstitute.org/eco...s2.html#maglev

to make life better for all people on Earth.

With unlimited clean power, these things are possible.

Setting aside the details of Mars Venus and Mercury for a moment, and
looking at the asteroid belt, most of the materials in the asteroid
belt are contained in 10 major dwarf planets;

Name Mass
(×10^18 kg)
Ceres 946
Vesta 259
Pallas 201
Hygiea 86.7
Euphrosyne 58.1
Interamnia 38.8
Davida 37.7
Eunomia 31.8
Juno 28.6
Herculina 22.9


This is a total of 1,710.6e18 kg of the asteroid's total 3,200.0e18
kg.

http://en.wikipedia.org/wiki/Asteroid_belt

It takes only a few days to get there at 1 gee

http://www.scribd.com/doc/60934836/Vesta-2

and requires a propellant fraction of 0.15152 of the total vehicle
weight. A 550,000 ton ship like that described above, would require
100,000 tons of propellant for a round trip.

But we must keep in mind that if we apply a small boost to an asteroid
of only a few km/sec we can cause it to drop in its orbit, down to
Earth's orbit. We can also have it collide with Earth or the moon,
and either litho-brake or aerobrake.

To figure out the minimum energy to get stuff from the Asteroid belt
to Earth we have to solve the Vis Viva Equation

V = SQRT((GMm)*(2/r - 1/A))

Here r = radius from sun, A=semi-major axis, G=gravity constant,
M=mass of sun, m=mass of object. Notice A is used for a different
variable in this equation than in the earlier equation.

Something in a circular orbit r=A so

V = SQRT(GMm/A)

Now, Ceres has a semi-major axis (r) equal to 2.7663 AU and it takes
4.6 years to get around the Sun. Plugging in This gives Ceres a speed
o 17.28 km/sec.

It takes Earth one year to get around the sun at 1.0000 AU so it is
moving at 29.86 km/sec.

NOTE: 2.7663 * 2 * pi() * 150 million km = 2,607.17 million km.
4.6 x 365.25 x 24 x 3,600 = 145,164,960 seconds
V =17.96 ~ 17.28 km/sec

(Ceres orbit is not circular)

NOTE: 1.0000 x 2 * pi() * 150 million km = 942.48 million km
1.0 x 365.25 x 24 x 3600 = 31,557,600 seconds
V = 29.86 km/sec

(Earth orbit is nearly circular)

To drop something from Ceres to Earth along a minimum energy transfer
then requires that you slow the speed down a little - and do so at the
right time.

This egg shaped or elliptical orbit meets up with Earth on one side of
the Sun, at 1.000 AU, and meets up with Ceres on the other side of the
Sun at 2.7663 AU. A total diameter of 3.7663 AU. This means the semi-
major axis - or half the diameter - is 1.8832 AU.

Now we have enough to use our Vis Viva equation;

V = SQRT((GMm)*(2/r - 1/A))

At Ceres: V = SQRT( 891.62 * (2/2.7663 -1/1.8832) ) = 13.08
km/sec
At Earth: V = SQRT( 891.62 * (2/1.0000 - 1/1.8832)) =
42.23 km/sec

Now, recall that Ceres is moving at 17.28 km/sec so the difference is
4.2 km/sec

And, Earth is moving at 29.86 km/sec so the difference here is 14.37
km/sec

Using our fusion rockets again, we only need

At Ceres:
u = 1 - 1/EXP(4.2/33000) = 0.00012726~ 0.013%

At Earth:
u = 1 - 1/EXP(14.4/33000) = 0.000436268 ~ 0.043%

A total of 0.056% This means that for each ton of lithium deuteriude
consumed using this technology, we can import to Earth 1,785 tons of
materials from the Asteroid belt!

Now, wealthy humans consume about 10 tons of raw material a year.
Well off humans consume about 3 tons. If we imported enough stuff to
let all humans live well - in the Earth/Moon system - we would need 85
billion tons of material per year. This requires 47.8 million tons
of lithium deuteride per year. This is nearly 5x the rate of
consumption to maintain a large population on the Moon.

So using Earth's oceans as a resource lasts only 100 years.

Now, the time it takes to get back to Earth is half the orbital period
of the minimum energy transfer orbit - about 15.5 months. This is
computed using Kepler's equations of planetary motion;

period = SQRT(A^3/mu)

mu=1 if a=Astronomical units and periods in years.

transfer = period/2 = SQRT(1.8832^3)/2 years --- 15.5 months

Also, we can only ship things for about a month when Ceres and the
Earth are in the right position relative to one another.

This is why we develop 10 asteroids at once! So we can get a constant
supply throughout the year.

We can develop the asteroids as quickly as we can develop the moon -
in less than 10 years.

Now, what about the supply of lithium? Deuterium is not really an
issue its so plentiful.

What do we do about that?

(1) We change up our reaction to use more plentiful materials,
(2) We tap into the resources of the asteroids.

Since we have everything we need to do this project, lets look at how
much lithium is likely to be in asteroids.

http://en.wikipedia.org/wiki/Abundan...mical_elements

About 3 lithium-6 atoms for every 1 million silicon atoms. Silicon
has an atomic weight of 28, lithium 6 has an atomic weight of 6. So,
this is 1 gram of lithium-6 for very 1.55 metric tons of silicon.

About 15% of the asteroids is silicon - so that 1.71e18 tonnes of raw
material in the 10 top listed asteroids mean 256.5e15 tonnes of
silicon is present. This means 16.5 trillion tons of lithium-6
deuteride are available in these 10 asteroids. This is 66x the amount
in Earth's oceans. So, these 10 asteroids represent sufficient
material to supply 8.5 billion people across the solar system with
enough raw material to sustain them at billionaire levels for 6,600
years!!

Longer than the period of time since the invention of cities and
writing.

Within this period it is very likely that better systems of energy use
will be developed.

Rather than have the ships accompany the cargoes for 15.5 months - it
makes sense to boost automated containers with a space tug - and then
capture them with another space tug at the receiving end. It also
makes sense to adjust costs so that high value cargoes can be sent all
year round. And, high gee flights - for human transport - anywhere in
the inner solar system in a matter of days.

We have the technical means and for the past 50 years have had the
technical means to do anything we like in the Solar System - to enrich
the lives of everyone on Earth while removing all industrial processes
off-world preserving our biosphere - living well without any adverse
impact at all.