News Ionic shielding against solar radiation tested

[Wishbone]

The bottom line seems to be: ionic shielding is not needed for our lunar outposts which will be semi-underground, constructed from (igloo-like?) or at least covered by regolith bricks.

 

[jedidia]

Neither "difficult" and "doesn't look encouraging" mean "impossible"

I meant exactly what I wrote

 

[JEL]

@T.Neo; yeah, you can't argue with the mighty dollar in any easy way

170 billion may currently be improbable to find for lunar mining, but atleast that kind of money is not impossible to find in government: http://www.reuters.com/article/idUSTRE66F21Q20100716

And after the initial investment, into building the railway or tube-gun launcher and furnaces and robotic mining-vehicles, the continued operation should be relatively low cost. If it could be made either fully automatic with no human presence needed on site, or atleast needing only remote-control from earth, the monthly bill shouldn't be a program-killer in itself. Nothing would be needed from earth after initiation if everything was driven by electric energy taken from the sun and both the mined ore and the glass-crates returning to earth were made of minerals from lunar-regolith. A self-sustaining program at best.

No one says the returning glass-crates should hold tons of ore. They could be like smaller brick-sized pellets shot from a tube-gun towards earth. Small light-weight automated mining machinery, and a lot of it, instead of huge mastodons of huge heavy iron, would be more efficient and cheaper to replace.

Well, we'll just have to put this into the sci-fi locker for now then, and take it back out if needed later

 

[jedidia]

the continued operation should be relatively low cost.

relative to the initial costs, sure. With our current technology they still will be a lot higher than any return you could ever hope for.

 

[JEL]

Well, we have to start somewhere, or else we wont get anywhere

 

[jedidia]

starting without an economically sound plan will only get you there and back again, and we already did that...

Either the reasons for getting back to the moon are economical, that means the operation pays for itself and brings some plus. Or the reasons are scientific, which means that a) we're willing to pay the whole dear price for whatever we want to research up there and b) we will take a totally different aproach to begin with. Getting heavy and expensive mining machinery up there if there's a 100% chance that they won't pay for themselfes is a very bad idea. Getting a big telescope up there for the same money would seem a lot more reasonable in this case.

 

[JEL]

If we don't need any of the moon's resources it will obviously never pay off to go there on a mining operation. It was sparked by the peak-oil debate, which is ofcourse speculation in the sense that we might not run into any trouble if workable earth-based alternatives to oil can be found before we actually run out (whenever that may happen, if even anytime soon).

 

[T.Neo]

Yeah, the problem is: the initial cost, is absolutely massive for such an operation.

You'll need some sort of manned presence, it won't be massive (as most equipment will be autonomous or radio controlled), but it will be needed to fix unforseen problems, etc.

And in addition of needing to ship people and their supplies to the Moon, spare parts, and items that cannot be manufactured on the Moon must also be sent. Even if you manufacture most of your infrastructure in-situ, there will still be things that will need to be shipped from Earth- things that coincidentally end up being some of the most critical components...

Radio operators, also do not work for nothing. Nor does their Earthside software, or the transmitters, etc...

No one says the returning glass-crates should hold tons of ore. They could be like smaller brick-sized pellets shot from a tube-gun towards earth.

Yes... what powers this tube gun? What is it made of? Where on the Moon is it placed? How is it constructed?

Your helium-3 bricks sound just about the right size to be extremely difficult to recover, especially without a mid-course correction...

Small light-weight automated mining machinery, and a lot of it, instead of huge mastodons of huge heavy iron, would be more efficient and cheaper to replace.

Yes, that is a nice notion, and an essential one, but the fact remains that you're going to have to bulk things up, machinery has to be durable, tough, to survive in that environment. They don't have to be big steel monsters, but they'll be... large aluminium beasts.

And they will still be very massive in total, and still relatively difficult/expensive to get to the Moon...

It was sparked by the peak-oil debate, which is ofcourse speculation in the sense that we might not run into any trouble if workable earth-based alternatives to oil can be found before we actually run out (whenever that may happen, if even anytime soon).

We shouldn't be worried about oil running out. We should be worried about oil production, and oil being an economic energy source.

Helium 3 as an oil solution doesn't make sense, since petroleum is primarily used for transport, whereas electricity production (the task of a fusion reactor) is mostly taken up by coal (which is also a finite resource).

While extraterrestrial sources of Helium 3 might be practical in the long term, they certainly aren't in the short term. We have to find solutions that are far less costly and problematic, not waste time on the Moon.

 

[RisingFury]

It might be because not enough power available. RTGs generate only few hundred watts of power. The artice said their prototype device draws as much current as electric kettle so it is ~2kW so it is too much power for deep space probes.

True... the field of a long straight coil is pretty low for the power you put into it - unless you use a superconductor. You probably couldn't use superconducting materials on probes because of cooling, but you could probably at least let your conductor cool down a bit by radiative cooling. It won't be superconductive, but it will lose resistance.

 

[Sky Captain]

We shouldn't be worried about oil running out. We should be worried about oil production, and oil being an economic energy source.

Helium 3 as an oil solution doesn't make sense, since petroleum is primarily used for transport, whereas electricity production (the task of a fusion reactor) is mostly taken up by coal (which is also a finite resource).

While extraterrestrial sources of Helium 3 might be practical in the long term, they certainly aren't in the short term. We have to find solutions that are far less costly and problematic, not waste time on the Moon.

IMHO energy resources will be one of the last things humans will start to mine from extraterrestrial sources. There are enough uranium and thorium on Earth to supply our energy demand practically indefinetaly even if massive growths of demand takes place. Even your average rock - the lowest grade ore contains ~2 - 3 ppm of uranium and 10 - 12 ppm of thorium, far more than lunar regolith has He3. With advanced fission breeder reactors fission is nearly as efficient energy source as fusion so it is likely it will be unprofitable to mine extraterrestrial energy resources for a very very long time.

First resources to be mined from moon or asteorids probably will be something that is very valuable in small quatities and neccesary for industry. Rare earth metals might be good candidates if we found extraterrestrial sources significantly more rich than Earth based sources.

 

[Wishbone]

Even cheaper than in China? Doubtful...

EDIT: just re-read the USGS report on REEs, the sentence above is slightly misleading due to China trying to squeeze the market.

 

[JEL]

the problem is: the initial cost, is absolutely massive for such an operation.

Look at the war-cost in the link I posted earlier, it's much much greater than Apollo's total cost, maybe even a whole order of magnitude greater, yet the money are being found by the government.
(http://www.reuters.com/article/idUSTRE66F21Q20100716)

So if spending a tenth, of what we've spent on the war, could get a mining operation going on the moon, which might also benefit us in further space-exploration, then we could debate if the cost is worth it or not. The Apollo-mission was considered worth it, and didn't break the bank.

In the end it's all about choices. What we want. Do we want the war, or do we want the moon?
It may never become reality if we only focus on getting gains for our own generation. If we focus only on short-term goals. But the moon is the most logical choice as the next step in human proliferation.

what powers this tube gun? What is it made of? Where on the Moon is it placed? How is it constructed?

Powered by solar-electricity and using electro-magnetism for payload-acceleration along either rails or inside a tube.
It's placed where it's needed, perhaps it could even be made mobile (we're operating in 1/6th earth-gravity), and placed by the initial human missions that go to construct the sites.

Check these videos for more inspiration on different systems and ideas:

[ame="http://www.youtube.com/watch?v=6nowIn-QdbE"]YouTube - electromagnetic launcher[/ame]

Your helium-3 bricks sound just about the right size to be extremely difficult to recover, especially without a mid-course correction...

Could be. I don't know the max-precision that can be achieved by something shot at earth from the moon. Maybe it can be countered somewhat by launching a lot of bricks. Or maybe we can only make it work if we have a heavy-launcher on the moon that shoots very big crates off. Or maybe it's only useful for launching vehicles that go to other planets, but are too big to be launched from Earth, such as perhaps a manned mission to Mars.

I'm not offering a finished shake'n'bake concept here, just some brain-storming ideas that might spark something (maybe something completely different)

Helium 3 as an oil solution doesn't make sense

You might be right. I don't know how mature the fusion-tech is yet.
:tiphat:

 

[GoForPDI]

In response to the OP - Very nice development, especially as part of it has been made at Strathclyde University, who I have applied for to do Aerospace and Mechanical Engineering.

All we need now is a manned mission into a high eliptical earth orbit to test it out in the VAB's.

 

[jedidia]

You might be right. I don't know how mature the fusion-tech is yet.

We're about 20 years away from a reactor that returns more energy than it consumes.

Problem is, we thought we were 20 years away from that for the last 50 years now... :shifty:

 

[T.Neo]

Look at the war-cost in the link I posted earlier, it's much much greater than Apollo's total cost, maybe even a whole order of magnitude greater, yet the money are being found by the government.
(http://www.reuters.com/article/idUSTRE66F21Q20100716)

So if spending a tenth, of what we've spent on the war, could get a mining operation going on the moon, which might also benefit us in further space-exploration, then we could debate if the cost is worth it or not. The Apollo-mission was considered worth it, and didn't break the bank.

Yeah. Thing is, people will spend money on war because they think it's necessary. People won't spend money on spaceflight because they don't. People don't choose, willy-nilly, to go to war. That is rubbish. People go to war because of grave situations, or to keep ahead in global geopolitics.

That money also can't come from nowhere, and it also does not have an insignificant impact. I don't think either Vietnam or the Iraq and Afghanistan wars were or are kind to the US economy...

In the end it's all about choices. What we want. Do we want the war, or do we want the moon?

Do we want war or do we want the Moon? When did this become a thread about going to war? :huh:

It may never become reality if we only focus on getting gains for our own generation. If we focus only on short-term goals. But the moon is the most logical choice as the next step in human proliferation.

Here's the thing: if nothing pays out in our generation, nobody cares. Planning for future generations is a very good idea, but it has to have some sort of immediate impact.

"The Moon is the most logical choice as the next step in human proliferation" is nice sci-fi rhetoric, but in the real world... notsomuch. Definitely not, when you can't get public support for a measly outpost.

If you're thinking long term, you really do want to look at Mars. The gravity is more than twice that of the Moon, the dirt won't melt your boots, and you're got an atmosphere from which you can suck carbon, hydrogen and nitrogen.

Powered by solar-electricity and using electro-magnetism for payload-acceleration along either rails or inside a tube.
It's placed where it's needed, perhaps it could even be made mobile (we're operating in 1/6th earth-gravity), and placed by the initial human missions that go to construct the sites.

Check these videos for more inspiration on different systems and ideas:

"Solar powered and operating by electromagnetism" are nice ideas, but the engineering reality is different. I can say that I want a High Velocity Interplanetary Passenger Spacecraft, with a total dV of 500 km/s and the capability to accelerate at 1G. I can say that it is Fusion Powered. Will it work? No. There is a big "something magic happens here" space.

I know the general concept. EMALS for one, is not near the velocity required, and I can't expect any such device to be easily transportable. In addition, if we are accelerating the daily requirement I put forth in my previous post with a launcher efficiency of 60% (which is probably way too high), it will require 725 m^2 of 20% efficient solar panels, providing they are pointed perfectly at the Sun. A system that will also be relatively hefty, and not very practical for mobility.

Could be. I don't know the max-precision that can be achieved by something shot at earth from the moon. Maybe it can be countered somewhat by launching a lot of bricks. Or maybe we can only make it work if we have a heavy-launcher on the moon that shoots very big crates off.

Yes. Launch a lot of bricks, with a lot of He3, which is mostly wasted, which creates a huge inefficiency in mining operations, which means that your mining machinery and refining plant will have to be so much bigger...

I already outlined the sort of "megalauncher", which would have to carry some 100 tons from the surface of the Moon. A 100 ton launcher, let alone a 100-ton capable reentry vehicle, has me in doubts...

Or maybe it's only useful for launching vehicles that go to other planets, but are too big to be launched from Earth, such as perhaps a manned mission to Mars.

How too big to be launched from Earth? I already explained, that it makes zero sense to launch from the Moon like that, because the infrastructure isn't there and won't be there for a very, very long time.

The ISS is 375 tons of mass that has been lifted into orbit over multiple launches. It is both not impossible to launch that mass, nor is it impossible to put it together in orbit and operate it. A lunar industry and an electromagnetic launch to accomodate that, on the other hand... is quite comical.

You might be right. I don't know how mature the fusion-tech is yet.

I can tell you that it isn't mature. And you certainly won't be using it to power cars, or airliners, or cargo ships. At least, not within 10 000 years...

All we need now is a manned mission into a high eliptical earth orbit to test it out in the VAB's.

That would just be a waste of money. A satellite with radiation monitoring equipment would be better. :shifty:

Problem is, we thought we were 20 years away from that for the last 50 years now...

Things are getting better as we go along though...

 

[JEL]

Yeah. Thing is, people will spend money on war because they think it's necessary. People won't spend money on spaceflight because they don't. People don't choose, willy-nilly, to go to war. That is rubbish. People go to war because of grave situations, or to keep ahead in global geopolitics.

I think you're confusing people with governments. We, the people, did not vote to go to war, nor did we vote to go to the moon. These decisions are all done for us by our representatives. If they are convinced the moon is worth going to, we'll go. But as long as they are not convinced, we'll not.

And my point with the war-cost was simply to exemplify that the government was able to raise 10 times more money than the Apollo-cost for something it decided to do.

Here's the thing: if nothing pays out in our generation, nobody cares. Planning for future generations is a very good idea, but it has to have some sort of immediate impact.

I think you're overly pessimistic. But if you're right and 'immediate' impact is required, then you should probably even kiss Mars more goodbye than the moon.

"The Moon is the most logical choice as the next step in human proliferation" is nice sci-fi rhetoric, but in the real world... notsomuch. Definitely not, when you can't get public support for a measly outpost.

If you're thinking long term, you really do want to look at Mars. The gravity is more than twice that of the Moon, the dirt won't melt your boots, and you're got an atmosphere from which you can suck carbon, hydrogen and nitrogen.

I disagree with you on this. The moon is more logical to begin with simply because it's much closer and simpler. Since establishing longer-term human presence on a different planet/moon is an unknown, there are bound to be surprises coming. Such surprises are much easier dealt with when reaction-times are low. An emergency-flight back home to earth, or an emergency-supply flight the other way, is clearly easier between earth-moon than earth-mars.

How will low gravity affect humans, for example. It makes little sense to start with a high-profile mission to Mars before we know some more about how humans are affected by staying on the surface of a low-gravity body. On the moon we can experiment much more efficiently in this area simply because unforeseen earth-moon exchanges can happen much more rapidly, such as, for example, launching new equipment based on experimental study by the people on the moon. On the moon we'll have a much higher degree of flexibility, it'll be easier to make un-scheduled changes as we go, than on Mars.

Mars is pretty much a fire-and-forget mission; once the flight is launched we can only sit back and hope we launched all the right stuff from the beginning and that nothing goes wrong or outside of plan (which is rather naive to expect)

Also the weather on mars, such as dust-storms, is a risk-factor. The moon 'weather' allows us to use some of our experiences from ordinary space-flight.

And the dust on Mars is just as much a risk-factor as that on the moon:

“Martian dust is a number one risk,” says Jim Garvin, NASA chief scientist at the Goddard Space Flight Center.

"Solar powered and operating by electromagnetism" are nice ideas, but the engineering reality is different. I can say that I want a High Velocity Interplanetary Passenger Spacecraft, with a total dV of 500 km/s and the capability to accelerate at 1G. I can say that it is Fusion Powered. Will it work? No. There is a big "something magic happens here" space.

I know the general concept. EMALS for one, is not near the velocity required, and I can't expect any such device to be easily transportable. In addition, if we are accelerating the daily requirement I put forth in my previous post with a launcher efficiency of 60% (which is probably way too high), it will require 725 m^2 of 20% efficient solar panels, providing they are pointed perfectly at the Sun. A system that will also be relatively hefty, and not very practical for mobility.

I don't know what magic you are talking about? As far as I know electro-magnetism is a proved technology?
And the velocities you can achieve are limited by power and rail-length more than anything else, in a vacuum on the scales we are talking about here, so lunar escape-velocity is hardly impossible to reach using magnetism.

Check this: http://en.wikipedia.org/wiki/Maglev_(transport)

Yes. Launch a lot of bricks, with a lot of He3, which is mostly wasted, which creates a huge inefficiency in mining operations, which means that your mining machinery and refining plant will have to be so much bigger...

I already outlined the sort of "megalauncher", which would have to carry some 100 tons from the surface of the Moon. A 100 ton launcher, let alone a 100-ton capable reentry vehicle, has me in doubts...

Ok, mining lunar resources for use on earth appears to be too big a task for it to be rational at this time. I agree it seems that way at the moment. Too bad.

I'll stick with the rest though; the moon as the primary objective for a longer-term human surface-presence on a non-earth planetary-body experiment, perhaps evolving into a permanent base, before considering sending humans to Mars.

How too big to be launched from Earth? I already explained, that it makes zero sense to launch from the Moon like that, because the infrastructure isn't there and won't be there for a very, very long time.

The ISS is 375 tons of mass that has been lifted into orbit over multiple launches. It is both not impossible to launch that mass, nor is it impossible to put it together in orbit and operate it. A lunar industry and an electromagnetic launch to accomodate that, on the other hand... is quite comical.

If it's comical you have atleast been entertained :tiphat:

I'm obviously talking about building the Mars-ship on the moon, not transporting it from earth to the moon just to launch it from the moon.
The rationale behind that is what I said above; that I think we need to experiment with a human surface-base closer to earth before trying such an experiment all the way over on Mars.
We need to learn how to actually build stuff on-site off-earth before we try to establish ourselves on Mars. The moon is ideal because it's so relatively close and simple.
In the process of this experiment I imagine we will then learn how to build the future human Mars-explorer space-ship we will need to go to Mars, and a sufficient rail-launcher for it. And THEN the vacuum of the moon will work to our advantage.

In my view it's much to early to consider Mars for human missions. You could prove me wrong ofcourse, and part of me does indeed hope you do (I would love to see humans go to Mars, make no mistake about that ). But if the moon is too expensive, then Mars can only be even more expensive.

I can tell you that it isn't mature. And you certainly won't be using it to power cars, or airliners, or cargo ships. At least, not within 10 000 years...

Ok, I can't see 10,000 years ahead myself so I'll just take your word for it.

 

[T.Neo]

But as long as they are not convinced, we'll not.

Yeah, well, what I'm trying to say is: they won't be convinced.

And my point with the war-cost was simply to exemplify that the government was able to raise 10 times more money than the Apollo-cost for something it decided to do.

Something that was viewed as very necessary to maintain a strategic geopolitical position during the cold war...

I think you're overly pessimistic. But if you're right and 'immediate' impact is required, then you should probably even kiss Mars more goodbye than the moon.

What immediate impact are you going to get from the Moon, that you aren't going to get from Mars?

Conversely, Mars is new, exciting, untrodden territory. The average Joe of 2040, is not going to care about going to the Moon, if someone announces a Moon program, he'll be all "yeah, but didn't we like, uh, go there in like, 100 years ago? What a waste of like, money, man."

Ok, so he won't care about going to Mars either, but he might care just a little more.

I disagree with you on this. The moon is more logical to begin with simply because it's much closer and simpler. Since establishing longer-term human presence on a different planet/moon is an unknown, there are bound to be surprises coming. Such surprises are much easier dealt with when reaction-times are low. An emergency-flight back home to earth, or an emergency-supply flight the other way, is clearly easier between earth-moon than earth-mars.

Yes. What are the surprises? Are we going to be attacked by Martian gloobersnatches?

You start small, and you work your way up. There are hundreds of ways to test technology and build skills for Mars, that do not require a hugely expensive, largely unrelated program on the Moon.

How will low gravity affect humans, for example. It makes little sense to start with a high-profile mission to Mars before we know some more about how humans are affected by staying on the surface of a low-gravity body. On the moon we can experiment much more efficiently in this area simply because unforeseen earth-moon exchanges can happen much more rapidly, such as, for example, launching new equipment based on experimental study by the people on the moon. On the moon we'll have a much higher degree of flexibility, it'll be easier to make un-scheduled changes as we go, than on Mars.

You could also test a lower gravity environment in LEO, with a rotating spacecraft. Now, that might be a bit bold, and it is, but it'll certainly be less cost and resource intensive than a Moon program, and it is technology that we will have to develop anyway (for example, it could pave the way for Mars transfer spacecraft, that prevent cardiovascular and muscoskeletal degeneration on the way to Mars itself).

In LEO if a problem occurs, you can return to Earth in a matter of not months, not days, but even minutes. And risk and cost from associated lunar hardware is lost.

You won't be staying on Mars for years at first anyway, Moon program or not. And a (relatively) short stay does not mean flags and footprints; that is based on mission architecture, economics and political will. Not mission duration, which will, understandably, be relatively brief at first. This would allow plenty of testing of physiological factors, without stranding the crew on the planet for months.

Mars is pretty much a fire-and-forget mission; once the flight is launched we can only sit back and hope we launched all the right stuff from the beginning and that nothing goes wrong or outside of plan (which is rather naive to expect)

It would be pretty stupid not to test the hardware unmanned first, don't you think?

I don't know the details or even if it's true or not, but I've heard that VASIMR even allows an abort from a Mars transfer trajectory...

Also the weather on mars, such as dust-storms, is a risk-factor. The moon 'weather' allows us to use some of our experiences from ordinary space-flight.

There is no weather on the Moon, only the conditions you get in open space, and interesting dynamics with the dust and the lunar atmosphere (as well as temperature exhanges etc from the Moon itself, but that's another matter).

Of course the weather on Mars is a problem. How do you expect to learn to cope with it in a place where it doesn't exist?

And the dust on Mars is just as much a risk-factor as that on the moon:

I never said it was not. Potentially something that can be mitigated both by dust resistant parts, and airlocks or something like the SuitPort. The design of the LEM meant that the astronauts tracked dust directly into the cabin, obviously any future design would try to avoid that.

It is also important to note that the dust dynamics (including the presence of wind) are totally different on Mars and the Moon.

I was actually referring to the temperatures on the Moon, and the temperature gradients that you can experience there.

I don't know what magic you are talking about? As far as I know electro-magnetism is a proved technology?
And the velocities you can achieve are limited by power and rail-length more than anything else, in a vacuum on the scales we are talking about here, so lunar escape-velocity is hardly impossible to reach using magnetism.

I am not talking about magic, I am talking about technology. Which is not magic.

I'm not talking about rail length, or velocity, or total input energy. I'm talking about the overall feasibility of the system.

I know about maglev. It's also a nice, futuristic concept. I don't think it has anything to do with a railgun other than potentially the mechanism by which it works.

Ok, mining lunar resources for use on earth appears to be too big a task for it to be rational at this time. I agree it seems that way at the moment. Too bad.

That isn't bad at all. Why do you think it is bad?

We have an entire planet of resources that we don't need to travel 384 400 kilometers to get to. And they're cheaper too...

We need to learn how to actually build stuff on-site off-earth before we try to establish ourselves on Mars. The moon is ideal because it's so relatively close and simple.
In the process of this experiment I imagine we will then learn how to build the future human Mars-explorer space-ship we will need to go to Mars, and a sufficient rail-launcher for it. And THEN the vacuum of the moon will work to our advantage.

Sure, we'll build stuff on Mars soon enough... bricks, sandbanks, try to establish a rudimentary industry maybe manufacturing simple earthmoving equipment or energy collection devices maybe.

But a spacecraft? I really don't intend to offend, but I can't help to get the feeling that you either underestimate the resouces required to build a spacecraft, or overestimate how well various mines, mills, and spacecraft construction facilities can be constructed in an entirely new environment hundreds of thousands of kilometers away from home.

We know right now how to build a Mars explorer spacecraft, and we will know in 20 years how to build a Mars explorer spacecraft 100 times better than we can do it today. But building such a spacecraft on the Moon, and launching it into lunar orbit?

Maybe we will figure that out, in 500 years time.

In my view it's much to early to consider Mars for human missions. You could prove me wrong ofcourse, and part of me does indeed hope you do (I would love to see humans go to Mars, make no mistake about that ). But if the moon is too expensive, then Mars can only be even more expensive.

It isn't about expense. It's about whether that expense is worth it.

Look, I'm not trying to say, don't go to the Moon. I'd love to see a manned presence on the Moon.

What I'm trying to say is there are paths to get to Mars that (can be) far cheaper and far more practical and straightforward than a dedicated Moon program.

Personally I have wanted to see a manned presence on Mars for most of my life, and I really hope, that I will be able to see it within my lifetime. And I fear that if we (as a collective humanity) get bogged down by an expensive and resource consuming Moon program, we will only see manned missions to Mars even only by the next century. By which time you and I will be long dead, save for some elixr of life.

My fear is that it'll become like the Shuttle; STS was also intended to pave the way for (eventual) Mars missions, and over time, the Moon and Mars missions (and even the planned space station, which we only get a (castrated) version of now, right around the retirement of the shuttle) were scrapped and forgotten. And it has happened already: Constellation has been scrapped before it even began.

Sure there's science on the Moon. But there's science on Mars too, and it's extremely exciting- indeed, I am sure many people would agree that it is far more exciting than studying some interesting impact breccia on the Moon...

 

[JEL]

Yeah, well, what I'm trying to say is: they won't be convinced.

I'm not really a big fan of politicians...

Something that was viewed as very necessary to maintain a strategic geopolitical position during the cold war...

In that case, what would be the political reason for going to Mars?
A few astronauts on a Mars-mission isn't going to make any geo-political difference on Earth.

While we're at geo-politics; Why do you think China is so interested in the Moon?
If the moon is all "been there, done that" triviality, then why would China be interested in it? (I'm no fan of politicians, but I'm even less of a fan of dictatorships, especially powerful and cunning ones)

U.S. Reps. Frank Wolf of Virginia, John Culberson of Texas and Robert Aderholt of Alabama all Republicans serving on the House Appropriations commerce, justice, science subcommittee that approves NASA's annual budgets joined California Republican Rep. Dana Rohrabacher in objecting to Bolden's trip in a letter sent to the NASA chief as he left town.

"As you know, we have serious concerns about the nature and goals of China's space program and strongly oppose any cooperation between NASA and China," the lawmakers wrote in the Oct. 15 letter to Bolden. "In light of the short notice and scant information provided before your departure to China, we respectfully request a full briefing with you upon your return."

What immediate impact are you going to get from the Moon, that you aren't going to get from Mars?

A Mars-mission is much slower-paced because of the high travel-time involved.

It takes 6 months just to get there before even the first bit of science can be started. Then if by that science something is learned that requires some new equipment shipped there that wasn't brought along in the first place... then that will take another 6 months to arrive. Then the next bit of science-work can begin... then something new is learned as a result of the new equipment installed... and then it's discovered that some other new equipment needs to be sent from Earth... again another 6 months waiting-period...

On the moon, however, each of these steps can be taken much faster, making the moon the perfect ' learner's planet '.
Then, when the technology have matured and gone through all the inevitable childhood diseases that follow, the mission-planners will have a much better chance of rooting out some of the 'lack-of-knowledge'-pitfalls a Mars-mission might otherwise end up in. They will have a pre-existing mission to base some of their decisions on, which is so much better than pure guess-work.

You won't be staying on Mars for years at first anyway, Moon program or not. And a (relatively) short stay does not mean flags and footprints; that is based on mission architecture, economics and political will. Not mission duration, which will, understandably, be relatively brief at first. This would allow plenty of testing of physiological factors, without stranding the crew on the planet for months.

If the idea is to go to Mars to just stay for a few days, then a Mars-mission makes little sense IMO. When we go to Mars it should be to stay for a reasonable amount of time. A stay long enough to warrant the long travel-time. I can't see us invest humans in a year-long mission just to have them stay on Mars for only 3 days. And since the longest stay on the moon was just a little over 3 days, we just don't have the experience yet on how to exactly plan a safe month-long stay on Mars.

What are the surprises? Are we going to be attacked by Martian gloobersnatches?

If I new the surprises that await, then they wouldn't be surprises

The surprises a Mars-mission might face, are those things nobody thought of before-hand because nobody had the experience to anticipate them. Like, for example, the surprising arsenic-bug recently found. Did you anticipate that one? I didn't. So surprises do happen, and you just don't want a stupid one to happen 6 months away from Earth if it could have been avoided by doing proper training on the Moon first.

There are hundreds of ways to test technology and build skills for Mars, that do not require a hugely expensive, largely unrelated program on the Moon.

You can't deny that the best experience come from experimenting in similar conditions. The empirical effects of a longer-term settlement on the ground of a planetary body, like the Moon or Mars, can not, to the best of my belief, be experienced while in orbit.

The fact is, we have not had any known human presence living on a space-body, other than Earth, for longer than 3 days. That effectively limits how mission-planners can plan for a Mars-mission expected to be much longer than 3 days.

It would be pretty stupid not to test the hardware unmanned first, don't you think?

I don't know the details or even if it's true or not, but I've heard that VASIMR even allows an abort from a Mars transfer trajectory...

2 aspects here;

#1: You can't test for unknowns. If you discover, while on Mars, that you need something you didn't know you would need when you left Earth, or if a problem arises that you hadn't anticipated before going, then what will you do?

That's why the moon is better to start with, to minimize the number of such potential risks to the lowest possible before going to far out. You don't want to first start the learning-process once you're out on the big mission, 6 months away from home.

#2: Testing the space-ship equipment can obviously be done without going to the moon. Just like it was done with Apollo before going to the Moon (except the LEM landing ofcourse). But the equipment that the people will need and use, for a lengthy period, on the actual surface, can not be realistically tested un-manned or in orbit.

There is no weather on the Moon, only the conditions you get in open space, and interesting dynamics with the dust and the lunar atmosphere (as well as temperature exhanges etc from the Moon itself, but that's another matter).

Of course the weather on Mars is a problem. How do you expect to learn to cope with it in a place where it doesn't exist?

You missed my point. The reason I called the moon simpler than Mars is exactly because there's no significant atmosphere on the moon. That's why a mission should start there IMO. On Mars there's not only dust to deal with, but also atmosphere. 1 thing at a time. On the moon it can be learned how to work the dust-problem. Thus minimizing dust as a risk-factor on the Mars-mission.

The Moon isn't likely to be teaching anything directly about Martian-weather I think. But since the Martian atmosphere is very thin, living on the lunar surface in vacuum could still be a good learning experience for how it will be on Mars (maybe more on a psychological level for the people going on these missions, rather than equipment-wise.)

I never said it was not. Potentially something that can be mitigated both by dust resistant parts, and airlocks or something like the SuitPort. The design of the LEM meant that the astronauts tracked dust directly into the cabin, obviously any future design would try to avoid that.

Exactly my point! Now imagine the Apollo-design had been sent to Mars first instead of the Moon. Then the dust-into-the-cabin problem (and the dust's abrasive effects on the airlocks and suits) would potentially have been much more dramatic. But because of this experience a repeat can be avoided on the Mars-mission. Learning such stuff is gold. You're even coming up with ideas yourself on how to work around these problems, because you're aware of the problems. Without the moon you, I, and most likely everyone else, would have been clueless. But now, because of this empirical experience with the moon, this danger can be minimized on future missions. And since the Mars-mission is going to be such a huge and long step, everything that can be done to make it work the FIRST time... failure is not an option... should be done.

So this is just a perfect example of why Mars is a pre-mature goal at this point IMO.

I am not talking about magic, I am talking about technology. Which is not magic.

I'm not talking about rail length, or velocity, or total input energy. I'm talking about the overall feasibility of the system.

I know about maglev. It's also a nice, futuristic concept. I don't think it has anything to do with a railgun other than potentially the mechanism by which it works.

The maglev track would have to be about 186 miles long for a 1 G constant acceleration to take you to lunar escape-velocity (5,324 mph). Or about 63 miles if a 3 G constant acceleration was used.

Admittedly that's quite long... and quite fast... :leaving:

Well, back in the box with that idea then... :blackeye:

That isn't bad at all. Why do you think it is bad?

We have an entire planet of resources that we don't need to travel 384 400 kilometers to get to. And they're cheaper too...

It's bad because it means mining can't be used as a political motivator to escalate the space-program, for one thing, and, for the second thing, because having a whole moon full of extra resources is always better than having none (you can never have enough cake )

Personally I have wanted to see a manned presence on Mars for most of my life, and I really hope, that I will be able to see it within my lifetime. And I fear that if we (as a collective humanity) get bogged down by an expensive and resource consuming Moon program, we will only see manned missions to Mars even only by the next century. By which time you and I will be long dead, save for some elixr of life.

My fear is that it'll become like the Shuttle; STS was also intended to pave the way for (eventual) Mars missions, and over time, the Moon and Mars missions (and even the planned space station, which we only get a (castrated) version of now, right around the retirement of the shuttle) were scrapped and forgotten. And it has happened already: Constellation has been scrapped before it even began.

Sure there's science on the Moon. But there's science on Mars too, and it's extremely exciting- indeed, I am sure many people would agree that it is far more exciting than studying some interesting impact breccia on the Moon...

Right I guess the overall conclusion of our talk will have to be that you are in love with Mars and I am in love with the Moon

 

[Wishbone]

Everybody is in love with Venus...

 

[T.Neo]

I'm not really a big fan of politicians...

Neither am I...

In that case, what would be the political reason for going to Mars?
A few astronauts on a Mars-mission isn't going to make any geo-political difference on Earth.

Obviously the Apollo program didn't make any geo-political differences on Earth?

While we're at geo-politics; Why do you think China is so interested in the Moon?
If the moon is all "been there, done that" triviality, then why would China be interested in it? (I'm no fan of politicians, but I'm even less of a fan of dictatorships, especially powerful and cunning ones)

Why do you think they are so interested in a space station? Or manned spaceflight?

It is because they can say "been there, done that". So they can enter the "big league", as it were.

The "serious concerns" about China's space program are really annoying, one would think, that cooperating with China would help relations between the two nations...

A Mars-mission is much slower-paced because of the high travel-time involved.

It takes 6 months just to get there before even the first bit of science can be started. Then if by that science something is learned that requires some new equipment shipped there that wasn't brought along in the first place... then that will take another 6 months to arrive. Then the next bit of science-work can begin... then something new is learned as a result of the new equipment installed... and then it's discovered that some other new equipment needs to be sent from Earth... again another 6 months waiting-period...

6 months? What propulsion system are you using, a hamster in a plastic ball?

Travel time is relatively brief on sociopolitical scales. And you also don't need a 6 month travel time...

On the moon, however, each of these steps can be taken much faster, making the moon the perfect ' learner's planet '.
Then, when the technology have matured and gone through all the inevitable childhood diseases that follow, the mission-planners will have a much better chance of rooting out some of the 'lack-of-knowledge'-pitfalls a Mars-mission might otherwise end up in. They will have a pre-existing mission to base some of their decisions on, which is so much better than pure guess-work.

No, the Moon program will suck up so much monetary and technological resources, that it will put any Mars mission plan onto the back-burner to potentially be forgotten about for decades...

If the idea is to go to Mars to just stay for a few days, then a Mars-mission makes little sense IMO. When we go to Mars it should be to stay for a reasonable amount of time. A stay long enough to warrant the long travel-time. I can't see us invest humans in a year-long mission just to have them stay on Mars for only 3 days. And since the longest stay on the moon was just a little over 3 days, we just don't have the experience yet on how to exactly plan a safe month-long stay on Mars.

So, if you can stay for 3 days, you can't stay for 5? Is it really that hard?

We've done many stays in open space on the order of many months, I seriously doubt that a three-week mission to Mars, for example, would be all that difficult or dangerous based on our 3 day experience on a totally different body...

If I new the surprises that await, then they wouldn't be surprises

The surprises a Mars-mission might face, are those things nobody thought of before-hand because nobody had the experience to anticipate them. Like, for example, the surprising arsenic-bug recently found. Did you anticipate that one? I didn't. So surprises do happen, and you just don't want a stupid one to happen 6 months away from Earth if it could have been avoided by doing proper training on the Moon first.

So now we're worried about arsenic bugs on Mars. Right. :uhh:

What proper training on the Moon is going to protect against problems during a Mars mission?

They're two different objects. Any training you could glean from the Moon, is far outweighed by the enourmous uneeded burden it places on the space program.

And actually life using arsenic, and alternate biochemistry in general, is no new idea.

You can't deny that the best experience come from experimenting in similar conditions. The empirical effects of a longer-term settlement on the ground of a planetary body, like the Moon or Mars, can not, to the best of my belief, be experienced while in orbit.

A lot of empirical effects of living in a closed space, with operating life support systems and interpersonal relations, for example, can be determined.

Don't nearly seven billion people already live on the surface of a planetary body?

The fact is, we have not had any known human presence living on a space-body, other than Earth, for longer than 3 days. That effectively limits how mission-planners can plan for a Mars-mission expected to be much longer than 3 days.

Which is really silly, because things should not be limited by a timeframe, in an unrelated example. Limits should be set by the best available experience that can be gained from many sources, as well as technological abilities and statistical analysis.

The requirements of keeping humans alive on Mars for 30 days, are entirely different from the requirements of keeping humans alive on the Moon for 3 days.

#1: You can't test for unknowns. If you discover, while on Mars, that you need something you didn't know you would need when you left Earth, or if a problem arises that you hadn't anticipated before going, then what will you do?

That's why the moon is better to start with, to minimize the number of such potential risks to the lowest possible before going to far out. You don't want to first start the learning-process once you're out on the big mission, 6 months away from home.

And the Moon can also not tell you everything. To learn everything about going to Mars, obviously, you have to go to Mars.

I never said that testing is not required. You can do a huge wealth of testing not only in LEO and cislunar space, and by unmanned test missions to Mars, but also even on the surface of the Earth itself...

#2: Testing the space-ship equipment can obviously be done without going to the moon. Just like it was done with Apollo before going to the Moon (except the LEM landing ofcourse). But the equipment that the people will need and use, for a lengthy period, on the actual surface, can not be realistically tested un-manned or in orbit.

Sure it can, especially when it has capabilities to be operated remotely. For example, you can even regard the ongoing MER missions as technology testing on Mars, and the upcoming MSL rover as well. We continue to learn how objects react to the Martian environment, in a cheaper and more relevant way than via a lunar mission.

And testing on the Moon will not give proper results because you are doing so in a vastly different environment. A habitat on Mars and a habitat on the Moon, for example, have to deal with different environmental effects and need to work in different ways to keep their inhabitants alive.

You missed my point. The reason I called the moon simpler than Mars is exactly because there's no significant atmosphere on the moon. That's why a mission should start there IMO. On Mars there's not only dust to deal with, but also atmosphere. 1 thing at a time. On the moon it can be learned how to work the dust-problem. Thus minimizing dust as a risk-factor on the Mars-mission.

What's so dangerous about the atmosphere? The atmosphere makes the dust problem worse, in ways you aren't going to learn about on the Moon.

We already operate vehicles and have people in a vacuum environment, in conditions that you might regard as more psychologically stressful as those on Mars or the Moon. And many people have stressful jobs or work in stressful environments... maybe it would pay off to study them.

Exactly my point! Now imagine the Apollo-design had been sent to Mars first instead of the Moon. Then the dust-into-the-cabin problem (and the dust's abrasive effects on the airlocks and suits) would potentially have been much more dramatic. But because of this experience a repeat can be avoided on the Mars-mission. Learning such stuff is gold. You're even coming up with ideas yourself on how to work around these problems, because you're aware of the problems. Without the moon you, I, and most likely everyone else, would have been clueless. But now, because of this empirical experience with the moon, this danger can be minimized on future missions. And since the Mars-mission is going to be such a huge and long step, everything that can be done to make it work the FIRST time... failure is not an option... should be done.

So this is just a perfect example of why Mars is a pre-mature goal at this point IMO.

Those were primitive days, and through robotic exploration we have a much better understanding of Martian regolith than any Moon mission could have given us.

You don't need to go to the Moon, to worry about tracking dust into the cabin. Go for a walk in the desert, and you will track dust back into your vehicle. Foresight might not be fully 20/20, but it's better than the multibillion dollar lunar glasses you propose, that prevent the wearer from seeing where they're going.

Don't try to compare Martian dust to lunar dust, it's different stuff... for one, wind is a major factor on Mars that causes weathering, in no doubt Martian dust is abrasive, but it will not have the same properties as lunar dust- at least, not exactly.

The maglev track would have to be about 186 miles long for a 1 G constant acceleration to take you to lunar escape-velocity (5,324 mph). Or about 63 miles if a 3 G constant acceleration was used.

Admittedly that's quite long... and quite fast...

Well, back in the box with that idea then...

So you want to launch the people with the railgun as well? :huh:

It's bad because it means mining can't be used as a political motivator to escalate the space-program, for one thing, and, for the second thing, because having a whole moon full of extra resources is always better than having none (you can never have enough cake )

That smells of greed, we should only take what we need.

Political pressure for space is nice... we don't need lunar resources though, not yet, not nearly. But we really ought to manage our resources at home in a better manner.

Right I guess the overall conclusion of our talk will have to be that you are in love with Mars and I am in love with the Moon

Yes, you see, you are just as biased by your personal beliefs as I am.

Don't get me wrong, I am in love with the Moon too... just not as much. :shifty:

Everybody is in love with Venus...

Well, Venus is hot and spicy. What with all the sulfuric acid and +400C temperatures...