No clear justification for manned return to moon

Some people see the moon as a stepping stone to Mars. I see the moon as a
destination in its own right. There is a great deal we can do on the moon
that would take a while. Everybody wants cheap access to space (CATS). If
we fail at that, there is still a possibility for cheap objects in space.
We would achieve that through mining and manufacturing in space -- either on
the moon or an asteroid. I would make that a higher priority than sending
men to the moon. I would send robots to the moon capable of building stuff.
What should they build? One option is habitats for humans. When humans are
able to stay for years, then humans will be more useful.

This is different from the leaked Bush proposal. He'll only be president
for another 1 or 5 years. We can start off with his plan and change course
later.

"Schrodinger333" wrote in message
...
For any major space effort to survive long enough to come to fruition
there
needs to be some sort of clear rationale diving it forward.

But you don't need a clear rational for continuing it.

During the Vietnam War, when somebody complained about agent orange, he was
told that there were no military departments in charge of ending programs.
The military continued to dump it without reevaluating their decision to
dump it.

SO the question is.....if we are going to send men back to the moon and also
to
Mars then what is the rationale? Why are we doing it? I see absolutely no
reason for sending men to the surface of the moon.


Because it is there, and if we don't do it, someone else will. Also think of
the propaganda, everytime someone looks at the Moon, he will see America.
Planetary scientists do have a sample return mission (for the purpose of
dating an impact basin) on their wish list, but that can be done robotically.
Another "wish" is for a network of seismometers on thwe moon to study the
moon's interior, but again that can be done robotically.

Take a look at the Martian rovers: it takes 9 days to get them ready to roll
and when they do, it takes them a full day to move 120 feet. Now how long would
it take an astronaut to go that same distance?

There is no commercial resource on the moon that would come close to paying
the costs of a manned base. Energy from Helium-3 would be so expensive that
nobody could afford it.

No helium-3 is expensive, but it produces alot of energy.

The most plausible justification is that the moon could be a stepping stone
to
Mars. In that case we should only send men to the moon if there is a clear
engineering need to test certain pieces of hardware prior to a mArtian
flight.
Given how different the lunar surface is from the Martian surface ( no
atmosphere, long nights, huge temperature swings) I doubt that testing
hardware
for Mars on the Moon is either practical or a good idea.

The fact that Mars has a thin atmosphere is of little importance in designing a
Mars Space Suit. The pressure difference between what an astronaut needs to
breath and a hard vacuum is just about the same as between that and the Martian
Atmosphere. I say we should design a space suit for Mars and use it on the Moon
and save some development costs in the process. Martian rovers should work on
the Moon just fine. A Mars Hab should be able to land on the Moon. The rockets
required for a Mars mission can also be used for a Moon mission. A nuclear
rocket for getting to Mars can also be used on a Moon lander.

I think Mars and Moon programs should be interlaced, we can produce more big
rockets for both, and in the time between launch windows to Mars, we can launch
missions to the Moon. Those big rockets would also be available to launch
missile defense platforms into orbit.

Tom

Mars is a long-term item that is unlikely to happen
in our lifetimes, IMO.

No, it can happen at the same time were going to the Moon. The Moon is not a
requirement for going to Mars, it is simply another destination as are the
Asteroids. Getting to the Moon requires almost escaping the Earth's
gravitational field. The Earth already travels around the Sun at a significant
velocity. You simply add to that velocity, once you've subtracted the the
escape velocity from your out bound vehicle. Any additional velocity you add to
that of the Earth around the Sun is used to get to Mars. The vast bulk of your
reaction mass is used to achieve orbit, a smaller amount is used to achieve
escape velocity. Low thrust, high efficiency engines become viable here since
they don't have to fight gravity away from Earth.

"TKalbfus" wrote in message
...
Mars is a long-term item that is unlikely to happen
in our lifetimes, IMO.

No, it can happen at the same time were going to the Moon. The Moon is not
a
requirement for going to Mars, it is simply another destination as are the
Asteroids. Getting to the Moon requires almost escaping the Earth's
gravitational field. The Earth already travels around the Sun at a
significant
velocity. You simply add to that velocity, once you've subtracted the the
escape velocity from your out bound vehicle. Any additional velocity you
add to
that of the Earth around the Sun is used to get to Mars. The vast bulk of
your
reaction mass is used to achieve orbit, a smaller amount is used to
achieve
escape velocity. Low thrust, high efficiency engines become viable here
since
they don't have to fight gravity away from Earth.

The life support requirements are different for Lunar and Martian missions.
There is a big difference between 3 days and 3 months. If you have supplies
waiting for you on the moon, then you don't need a lot of supplies on a moon
ship. It can be pretty Spartan and still functional. Other people in this
newsgroup might be able to tell me how much bigger an Martian ship would
have to be. If you had to add radiation shielding to a Martian ship, that
would add a lot of weight.

Those who talk about space manufacturing need to think very carefully about the
manpower requirements involved. Most manufacturing plants need dozens or
hundreds of people to run them, and depend on a network of suppliers employing
thousands more. Space manufacturing is going to be exceedingly limited.

Think of something you could do in your garage or kitchen on the weekends.
PRoduction of sophisticated mechanical or electrical devices is out of the
question. Simple chemical processing is more like it. Turning excess government
rations into moonshine is probably feasible. ;-) How would running an
electrolysis and liquefaction plant producing LOX from water ice compare to
running a moonshine operation? Could it be done with the same amount of labor?
How about spare parts and repairs? Perhaps. If you can't set it up and run it
in your garage in your spare time then it's probably not going to be feasible
for a space base.

SPace manufacturing will probably be limited to basic products like LOX , LH2
and water and will only be possible in places where there is easily minable
water ice. Before we commit to a moonbase we send a robotic mission to look
for water first.

I'm a little sceptical about how far the Chinese space program will go. Putting
a man in orbit is all very well, but a man on the moon is a huge step beyond
that both technologically and financially.

I don't agree that the same equipment can be used on both the moon and
mars......taking your space suit example, mars gravity is much stronger than
lunar gravity, which is going to force you to adopt a much lighter weight
design for the mars suit. Sunlight on the moon is more intense, and the
operating temperatures will be different.

When it comes to landers the presence of an atmosphere means you can use
parachutes but it also means that you will need a heat shield. Delta-v will be
different. Mars landers need to worry about winds and avoiding all those
Martian boulders. The legs will have to be mechanically stronger because
Martian surface gravity is higher. WHen you add it all up I think you are
looking at two quite different designs with maybe a few shared components.

The different surface gravities (0.4 g versus 0.25 g IIRC) will have all sorts
of mechanical design implications for both rovers and habs. THings will weigh a
lot more on Mars. THe longer lunar night ( 14 days versus 12 hours) will have
lots of implications for power systems and thermal design. Ditto for the higher
daytime temps on the moon.

Finally the presence of resources on mars which can be turned into rocket fuel
will likely lead to a different mission architecture.

Put it all together and I fear you are looking at very different designs with
maybe a few shared concepts and components.

"Schrodinger333" wrote in message
...
Those who talk about space manufacturing need to think very carefully
about the
manpower requirements involved. Most manufacturing plants need dozens or
hundreds of people to run them, and depend on a network of suppliers
employing
thousands more. Space manufacturing is going to be exceedingly limited.

Think of something you could do in your garage or kitchen on the
weekends.
PRoduction of sophisticated mechanical or electrical devices is out of the
question. Simple chemical processing is more like it. Turning excess
government
rations into moonshine is probably feasible. ;-) How would running an
electrolysis and liquefaction plant producing LOX from water ice compare
to
running a moonshine operation? Could it be done with the same amount of
labor?
How about spare parts and repairs? Perhaps. If you can't set it up and run
it
in your garage in your spare time then it's probably not going to be
feasible
for a space base.

SPace manufacturing will probably be limited to basic products like LOX ,
LH2
and water and will only be possible in places where there is easily
minable
water ice. Before we commit to a moonbase we send a robotic mission to
look
for water first.

There would be a sizable labor force, but in the early stages, all of that
labor force would be on Earth. I'm not a water first person. In order for
mining and manufacturing to work, robots have to function. I'm concerned
about their needs and I don't think they need that much water. They would
need electricity, so you need that before you need water. If you can land
humans on the moon, then you can land fairly sizable robots on the moon.
You can land full sized bulldozers and trucks.

I apologize if this is a repost, but I don't see my post here.

"Schrodinger333" wrote in message
...
Those who talk about space manufacturing need to think very carefully
about the
manpower requirements involved. Most manufacturing plants need dozens or
hundreds of people to run them, and depend on a network of suppliers
employing
thousands more. Space manufacturing is going to be exceedingly limited.

Think of something you could do in your garage or kitchen on the
weekends.
PRoduction of sophisticated mechanical or electrical devices is out of the
question. Simple chemical processing is more like it. Turning excess
government
rations into moonshine is probably feasible. ;-) How would running an
electrolysis and liquefaction plant producing LOX from water ice compare
to
running a moonshine operation? Could it be done with the same amount of
labor?
How about spare parts and repairs? Perhaps. If you can't set it up and run
it
in your garage in your spare time then it's probably not going to be
feasible
for a space base.

SPace manufacturing will probably be limited to basic products like LOX ,
LH2
and water and will only be possible in places where there is easily
minable
water ice. Before we commit to a moonbase we send a robotic mission to
look
for water first.

There would be a sizable labor force, but in the early stages, all of that
labor force would be on Earth. I'm not a water first person. In order for
mining and manufacturing to work, robots have to function. I'm concerned
about their needs and I don't think they need that much water. They would
need electricity, so you need that before you need water. If you can land
humans on the moon, then you can land fairly sizable robots on the moon.
You can land full sized bulldozers and trucks.

"Schrodinger333" wrote in message
...
I'm a little sceptical about how far the Chinese space program will go.
Putting
a man in orbit is all very well, but a man on the moon is a huge step
beyond
that both technologically and financially.
Like .. 7 year step ?

-kert