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rootone
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Establishing such an infrastucture is not technically impossible, but I think 'It's a waste of time and resources' would be most people's opinion.
Generally I agree, though in that prospectus there still is no short-to-medium-term prospect of moon telescopes being as cheap or as valuable as in space.jkn said:We need in this order:
1: Cheaper access to orbit. Not much can be be done before this.
2: Permanently manned space station with:
- Radiation protection.
- Energy, air, water and food production.
- Production of basic construction materials: metals, glass, ...
Moon is best place for first station, because of fast escape to Earth and because most work can be done remote controlled from Earth.
After this moon telescopes become reasonable. Heavy parts can be made on the Moon and service is available when something breaks. Again most work can be done by remote control from Earth.
When moon base is well tested, it can be copied to martian moon and to asteroids. Mercury perhaps. Venus no.
That's why I wrote: Heavy parts can be made on the Moon. There is no point trying to make all parts on the Moon.tom aaron said:Made on the Moon! Do you have any idea of the technological infrastructure needed to make some hi tech part for a telescope? Let alone install it. Test it. Remove. Retest, etc.? There is a reason the JWST is a decade behind schedule.
jkn said:That's why I wrote: Heavy parts can be made on the Moon. There is no point trying to make all parts on the Moon.
JWST cannot be completely tested before launch. After launch it cannot be fixed. This greatly increases cost and build time.
First we need cheaper access to orbit. Then infrastructure on the Moon.
That's why I wrote: "in that prospectus there still is no short-to-medium-term prospect of moon telescopes being as cheap or as valuable as in space."jkn said:That's why I wrote: Heavy parts can be made on the Moon. There is no point trying to make all parts on the Moon.
JWST cannot be completely tested before launch. After launch it cannot be fixed. This greatly increases cost and build time.
First we need cheaper access to orbit. Then infrastructure on the Moon.
Jon Richfield said:You say: "JWST cannot be completely tested before launch. After launch it cannot be fixed. This greatly increases cost and build time".
At best all of that applies even more strongly to the moon-pool telescope, and any other substantial lunar-based telescope, and what is more, for JWST it isn't even all true:
you said "After launch it cannot be fixed", knowing full well that Hubble not only got fixed in space, but even got maintained and upgraded in orbit. What possessed you? You knew that perfectly well, right?
tom aaron said:Cheap access to orbit? It's not access to orbit. It's manned presence in space that is expensive...thefails safe infrastructure to support a human. The fuel was less than one thousandth the cost of a Shuttle flight...the rest was making sure astronauts did not die.
Putting some crew on the Moon to install or service a telescope would cost tens of billions of dollars.
With this I must sympathise,because I have long contemplated alternatives to rocket launches and am convinced that we could already be working on cheaper, more efficient, and safer options. I see very little sign of any initiatives of the type though.jkn said:If we manage to build a rocket which can be used like an airplane (return to launch site, quick service, refuel, fly again), then situation changes.
Personnel on moon base will not be there only to service one telescope.
jkn said:What possessed me? Knowledge. I was writing about JWST.
Tell me about it!Design of a moon base would not fit in a single forum post:
I fully agree. Read what I said above "...accident of history, part of the long-term consequences of a space programme..."First step must be cheaper access to Earth orbit. Without it we cannot even start.
Tell me ALLLLL about that when you have shown us how easy it is to do such things. You don't have to go to the moon for a first try just to convince me, just build yourself a few solar furnaces to produce the sorts of parts you would need for the colony buildings (never mind the telescope).I don't believe separating metals from moon dust or making glass is very difficult. Those materials are needed to expand moon base. Same materials can be used to make heaviest parts of telescopes. We should build Moon base before attempting to go any farther.
Right. So will our first bulk delivery of lunar green cheese. On current showing I wouldn't bet on anything of the kind this century.When we have manned moon base, building and servicing moon telescopes becomes reasonable.
If it would be easy, raw materials on Earth would be cheaper. Compared to Moon we have way better options to build separation-factories, but rare materials are still very expensive. If you calculate the net work of an average cubic kilometer of earth, you get something like billions of dollars. So why does it cost nothing to buy a cubic kilometer of Earth in the middle of a desert? Well, processing this costs much more than a billion.jkn said:I don't believe separating metals from moon dust or making glass is very difficult. Those materials are needed to expand moon base. Same materials can be used to make heaviest parts of telescopes. We should build Moon base before attempting to go any farther.
SpaceX will try it again (with the first stage) tomorrow, and they plan to re-use the second stage in the future, too. That can be game-changing (unfortunately, it would also give them a quasi-monopoly).jkn said:If we manage to build a rocket which can be used like an airplane (return to launch site, quick service, refuel, fly again), then situation changes.
Jon Richfield said:Tell me ALLLLL about that when you have shown us how easy it is to do such things.
That isn't a real need and even if it was, there isn't anywhere else in the solar system that can support anything but a tiny fraction of Earth's population.jkn said:A: Never expand to space. Stay on Earth until some natural or man made disaster kill us all.
mfb said:SpaceX will try it again (with the first stage) tomorrow, and they plan to re-use the second stage in the future, too. That can be game-changing (unfortunately, it would also give them a quasi-monopole).
If it would be easy, where is the autonomous machine on Earth that can extract metals (anything) out of rock? In particular, without a constant supply of chemicals from elsewhere?jkn said:Why should I explain how we separete metals from ore? We both know we can do it. We have produced metals thousands of years (at least gold, silver, copper, tin, iron and lead). So that is not enormously difficult.
Why was that not an option for Biosphere 2? Everything that works on the moon is so much easier here on Earth.jkn said:2: One problem Biosphere 2 had was too heavy work load for inhabitants. Work load in Moon base can be reduced by remote controlled equipment.
Thanks, I forgot that English uses two different words (both are "Monopol" in German).atyy said:What, what? Before the LHC?![]()
Not enormously difficult?jkn said:Why should I explain how we separete metals from ore? We both know we can do it. We have produced metals thousands of years (at least gold, silver, copper, tin, iron and lead). So that is not enormously difficult.
You appear to think that that means that if we send a machine with Earth comms and controls to the moon, then all we need is to look at our control screen while it picks up 100 pebbles, takes out the ten iron ones, the 7 Al ones and the 6 Mg ones, and discards the unwanted 75 pellets of oxygen, Si and so on?Lunar 'soil' = regolith with grain size 1 cm or less:
12% iron
7 % aluminum
6 % magnesium
Do you really claim that we cannot design machinery to separate those?
Collecting this 'soil' could be done with small remote controlled (from Earth) machinery.
Before quoting journalists' headlines on technical matters so glibly, you should read and understand the content as well. If you had done so you wouldn't have revealed your undone homework so vividly.Manufacturing complex parts is not that hard. 3D printed parts for rocket engines are tested. Jet engine made completely from 3D printed parts has been tested.
To be precise, you do not get any O2 from regolith at all. You get a lot of chemically stable oxides. Until you can explain why that makes a difference, forgive me if I ignore your views on the point. That isn't even industrial chem 101; it is lower high school concept material.From regolith we also get some He3 and lot of O2.
Nonsense. In the light of present knowledge, it would be nutty to go elsewhere via a moon base in the next century or so.Strongest reason why we need to build permanently manned moon base:
If we are ever going to build manned station anywhere farther away, we need first to build moon base.
This is a joke, riiight?1: Escape from Moon base to Earth takes couple days. From anywhere else couple years or more.
Get real mate! If that were true, why couldn't we use remote controlled equipment in Biosphere 2? Or even locally controlled? Once again you show a need to do some homework and find out why B2 didn't work and why we had better find out what to do about it before making fools of ourselves killing our space pioneers.2: One problem Biosphere 2 had was too heavy work load for inhabitants. Work load in Moon base can be reduced by remote controlled equipment.
Here for a change I agree. In fact I predict that is the future for Homo sapiens and possibly even for life on Earth. As I am getting tired of saying (not to you in particular) the reason that will happen is that we are apes and not termites.A: Never expand to space. Stay on Earth until some natural or man made disaster kill us all.
A little of that might happen, but the moon being a sterile objective, much like Mars, we would be fools to waste too much time on it, and unless our technology changes radically, we would be even bigger fools to waste more than we can avoid on anything resembling permanent bases there.B: Build Moon base and use technology tested there to build bases elsewhere.
This one has merit because it can be preceded by exploratory investigations that could reveal whether any of the bodies in question had anything to recommend it. And a lot of valuable work could be done in the process. After that we could get down to serious projects.C: Ignore Moon and go directly to asteroids or elsewhere.
For a start, forget help from Earth until we are in a position simply to lift off with adequate resources at a day's notice.C is slower and more expensive than B, because:
- Help is years away instead of days. So everything must be more reliable. That costs and increases development time.
- Remote controlled, by Earth, tools are not available. So more automation is needed making technology more complex. Complex tech that certainly works without complete testing...
Risks and costs are reduced by taking shorter steps. If we take too long step and fail, we will waste decades before trying again.
Do tell, do tell! Silly of all those dumb rocket engineers. Fortunately they didn't have a lot of politicos to queer the pitch for them... <siiiiigh!>Instead of Space Shuttle we should have made first stage of Saturn V reusable.
russ_watters said:That isn't a real need and even if it was, there isn't anywhere else in the solar system that can support anything but a tiny fraction of Earth's population.
While it would be cool to have a moon base and the spirit of exploration is cool, there is no chance of that being reason enough for people to be willing to spend trillions of dollars on something that has little tangeable value.
mfb said:If it would be easy, where is the autonomous machine on Earth that can extract metals (anything) out of rock? In particular, without a constant supply of chemicals from elsewhere?Why was that not an option for Biosphere 2? Everything that works on the moon is so much easier here on Earth.
Jon Richfield said:This is a joke, riiight?
Please give a reference for claims like this, otherwise the discussion has to end here. Unsourced speculation is against the forum rules, and you make a lot of claims without citing any sources. That is not how this forum works.jkn said:Automation is needed on asteroid station. On moon station remote control from Earth is enough. This is one reason why we should practice with Moon station first. All chemicals can be recycled.
Non sequitur and the unspoken premises are debatable if even that were logical.jkn said:About money I agree. But this solar system has resources for much larger population than Earth has now. Need to go there is not immediate.
Remote control with a transmission delay of over a second each way would only be practical for a few types of tasks, and you can't practise automation by playing with remote control anyway. A bit deeper thinking please!Automation is needed on asteroid station. On moon station remote control from Earth is enough. This is one reason why we should practice with Moon station first. All chemicals can be recycled.
Never mind other-planet rescue; think of just our backyard moon colony or whatever it might be. "Hey Mabel! Seems those guys in Tranquillitatis construction site got themselves into a mess. When is the next launch window? Thursday? Got a craft ready? Oh well, when then? No, not that one, it can't accommodate all of them. Hey you guys up there, how long can you hold out? Two days? Oh well never mind then..."1: Escape from Moon base to Earth takes couple days. From anywhere else couple years or more.
I believe you agree that we can get from Moon to Earth in couple days. So how can escape time from Mars or asteroids be shorter than 2 years? That 2 years includes necessary wait for launch window. You cannot do it faster with current engines. From Venus time might be shorter, but that is last place to go. Manned mission to Mercury is not possible with current engines.
You don't need launch windows on moon. Keep a spacecraft ready that has supplies for a few days for the crew. It can go to moon orbit at any time, go from there to a transfer orbit, enter the atmosphere of Earth within three days and land. One day more in moon orbit allows to choose from a large range of landing spots if necessary. The ISS has a similar system with the Soyuz that stay attached to it.Jon Richfield said:Never mind other-planet rescue; think of just our backyard moon colony or whatever it might be. "Hey Mabel! Seems those guys in Tranquillitatis construction site got themselves into a mess. When is the next launch window? Thursday? Got a craft ready? Oh well, when then? No, not that one, it can't accommodate all of them. Hey you guys up there, how long can you hold out? Two days? Oh well never mind then..."
You seem to have a very simplistic view of moon launchings and the sort of preparations you need for rescues that you haven't even bothered to characterise yet. We don't even succeed with mine, earthquake, flood, cave, and submarine rescues on Earth, and you seem to think that lunar rescues are just taxi jaunts? And that three days would suffice for unscheduled rescues, and that that would be fast enough even if we could manage it?mfb said:You don't need launch windows on moon. Keep a spacecraft ready that has supplies for a few days for the crew. It can go to moon orbit at any time, go from there to a transfer orbit, enter the atmosphere of Earth within three days and land. One day more in moon orbit allows to choose from a large range of landing spots if necessary. The ISS has a similar system with the Soyuz that stay attached to it.
Transporting astronauts to the escape vehicle can be tricky, but that is independent of the object you are considering. The time to get home is significantly shorter from moon.
No I don't think so. But you can make the necessary preparations. And you probably want that unless the moon base is so large that a quick rescue won't be feasible (or necessary).Jon Richfield said:and you seem to think that lunar rescues are just taxi jaunts?
That was never part of the discussion.Jon Richfield said:and that that would be fast enough even if we could manage it?
I fully agree with you on those points, and I don't see the relevance of them for the discussion how long it would take to reach Earth from moon.Jon Richfield said:are part of the reason why telescopes in orbit, and even colonies in orbit would make more sense than on the moon.
There is no need to get personal.Jon Richfield said:I hope to goodness that whoever plans our space future takes the whole matter of technicalities and objectives a LOT more seriously than you do.
that, unfortunately became a dismal failure, exploded a couple of minutes after launchmfb said:SpaceX will try it again (with the first stage) tomorrow, and they plan to re-use the second stage in the future, too.
Yes. I was not in any way involved,except for being on the same planet more or less, but it still was so painful that I am thinking about other stuff.davenn said:that, unfortunately became a dismal failure, exploded a couple of minutes after launch
Dave
Though I am compelled to admit the persuasiveness of your point in the light of that event, we need to see this as a statement on our current status and our need to advance, not necessarily a condemnation of our future prospects in space.Chronos said:The recent launch failure of the ISS resupply mission merely reaffirms our technological ineptitude. God forbid we should ever be compelled to launch multitudes of nuclear missiles to divert a wandering space rock.
Old thread, but there must be some other objection to a solution via relay satellite in lunar orbit (~2 hour period), or http://www.labspaces.net/pictures/blog/4cd8b1c15732e1289269697_blog.jpg? Forty posts in and I've not seen the objection yet.HallsofIvy said:Let me add another point- the moon keeps one face pretty much toward the earth. If we put a telescope on the moon on this side, most of the "visible sky" would be the earth. If we put it on the other side, we would have major problems with communicating with it, getting its images and controlling it.
If you had infinite funds to spend on a telescope, sure, put a dozen of them of the Dark Side of the Moon and launch a bunch of relay satellites. But, since you have only limited funds, the question must be asked: what would you see thru a telescope from the DS of the Moon that you wouldn't be able to see thru a telescope in Earth orbit? The telescope in Earth orbit is easier to maintain, since you don't have to send the Maytag repairman to the Moon every time something breaks down.mheslep said:Old thread, but there must be some other objection to a solution via relay satellite in lunar orbit (~2 hour period), or http://www.labspaces.net/pictures/blog/4cd8b1c15732e1289269697_blog.jpg? Forty posts in and I've not seen the objection yet.
mheslep said:As the hundred posts or so in the thread discuss, there are many problems with a lunar scope, but I don't think communication with the dark side is an intractable one.
mheslep said:I don't think communication with the dark side is an intractable one.