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NASA Has Plans for 2nd Space Station at L1
Keith Gabryelski writes "New Scientist has an article on NASA's unveiling of a "blueprint for the future" of space exploration. It entails a Space Station 5/6ths of the way to the moon. In other news, radiation sheilding on the space station isn't so good."
radiation sheilding on the space station isn't so good.
but my tan is great!
With the insane ammounts of cost overruns and mismanagement in the ISS project, who thinks that a jaded congress is going to vote a new space station [no matter how much MORE useful than the ISS it may be] any funds whatsoever?
There is only room for three people for extended stays, due to Congressional budget cuts in the habitation module and escape vehicle. The original intention is seven people. That means the crew of three must spend 75% of their time in maintenance with only a small amount for experiments and other innovation. Unlikely the current administration will increase funding. Many republicans hate NASA because of its environmental monitoring programs. And the previous scientific leader of NASA has been replaced by an accountant (cut and slash).
The new IMAX movie about the first three years of space station construction is fascinating.
"If you sent two people to Mars, one of them would die," says Marco Durante of the Federico II University in Naples
I think the key to preventing this is to pack enough food that the astronauts are not forced to resort to cannabalism.
The explorer part of me is saying, "Yay! It's about time we started building more structures in space. The Lagrange point would make a good neutral spot halfway to the moon." But then the realist in me says, "Given that NASA has proven that it can't stick to a budget, how much is this overrun going to cost?" And the article agrees with me.
Government is not the answer to promoting outer space as a new resource -- market forces have shown to be the driving force in all new ventures. We need competition in getting things into orbit, tourism to build hotels, industry to build fab plants, mining on the moon...
From a physics standpoint, getting men and material to and from the Lagrangian points would be vastly cheaper than getting them to and from the moon. Until we could utilize the raw materials of the moon to produce things, it isn't going to be cost-effective to have a moon presence.
Someone file a patent on flying to the moon! I can see NASA paying some major royalties.
Fault loves the past, worry loves the future, but content enjoys the present.
Why not just build on the moon?
Apples and oranges. Having a station in zero gravity is really useful for launching probes and ships from, and as a gateway between the Earth and the rest of the solar system. Having a moonbase gives you mining capabilities and so forth.
They're both very important aspects of stepping into space, for different reasons.
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
After the Sun and Moon. Its been fascinating to watch it get brighter as they add more cylinders and panels every year.
The station is visible in the evenings about one week a month and mornings one week a month, so the orbit can wobble over the US, Russia, Europe, and Japan. Sky & Telescope (set zip code, click on almanac) shows pass times & locations, as do other websites.
If i'm to be modded down for offtopicness, well, I deserve it, but I need to get this off my chest:
.00001% deviation from expected results researching *.*, right after they make clear that most likely it's due to faulty measurement equipment, New Scientist will publish that they found aliens, that they have a draft of the alien invasion plan, that Einstains's GToR is therefore void, and that in fact he himself WAS an alien trying to distract us from the truth. And then they _really_ start speculating and tell you that they infer from the inforamtion that Einstein was a shape shifter and that he was also the first husband of Melinda Gates.
/.er's comments than NS (if you can believe that!)
I simply can't read new scientist anymore. When the site actually loads (regardless of slashdotting), every single article they publish seems to be the scientific equivalent of the paparazzi.
I mean, really, one thing is to have a non-peer-reviewed magazine, and an entirely different thing is to intentionally publish exagerated, ridiculous, absolutely un-proved (and almost always un-provable) "facts". Even the simplest of stories is spinned beyond recognition. If a story comes up of some scientists spotting a
Now, I haven't read this article (not that I could even if I wanted to, NS' site goes DoS when they're linked from my cousin's non-porn website), but I'm sure I'll get more substance out of
There are two kinds of people in the world: Those with good memory.
Why not just build on the moon? Why stop at 5/6 the way to the moon?
Because the whole point of staging at L1 is that it allows low-energy transfers to other points in the solar system. Launching a trip to Mars, for example, from L1 would require much less energy than from either the surface of the Earth, or low Earth orbit, or the surface of the moon.
Of course, this ignores the biggest problem with the L1 point: it's unstable. A body placed at L1 will tend to either fall inward toward the Earth or outward toward the moon at the slightest push. Any space station at L1 will have to correct its position regularly, probably using simple chemical rockets. These rockets will have to be refueled periodically and so on, making for a nontrivial amount of effort to keep an L1 space station in position.
The L4 and L5 points, on the other hand, are gravitationally stable. If a body at L4 or L5 starts to drift out of position-- due to a collision or outgassing or whatever-- the Earth-moon system will tend to pull it back to the point of stability again. But since L4 and L5 are farther from Earth than L1 is, it takes more time and energy to get there from LEO.
I write in my journal
The time between when Columbus "discovered" the new world and Magellen circumnavigated the globe was 30 years. It has now been 30 years since Apollo 17, the last time man visited the moon, the last time man left low earth orbit. I think it's a great failure of our race that we've dragged our feet such.
To think that technological advance is blazingly fast in this day in age is misleading. We're not doing too well at hitting the important targets. NASA might just now be waking up to this, but it's yet to be seen if their budget wakes up to it. (Nasa funding was 4% of the national budget at the height of the Apollo program, it's less than 1% now)
So I applaud their very recent efforts to finally mention some vague goals away from Low Earth Orbit. L1 is a fine stepping stone, but Mars is where the public eye is. Nasa administrator Daniel Goldin had some brave words about the possibility of sending men to Mars in this decade or the next, but Bush put a bean counter in charge of Nasa pretty quickly to throttle cost overruns from the ISS.
What we really need is a president giving NASA a kick in the pants, and the funding to follow, as Kennedy did. Either that or wait around for private space exploration to become worthwhile, and we're going to be waiting quite a while in that case. Another space race? maybe China? I hope so. Because the current NASA schedule is anything but ambitious.
a space station at a LaGrange point (in this case L1) wouldn't have to use thrusters to maintain a stable orbit and would never leave it's stable orbit around the earth
That's not true. L1, L2, and L3 are all gravitationally unstable points. A space station at L1, if nudged out of position even slightly, will tend to spiral inward toward Earth or outward toward the moon. The L4 and L5 points are the only stable Lagrangian points in a two-body system.
I write in my journal
To the tune of "Home on the Range"
Home on Lagrange
Oh, give me a locus
Where the gravitons focus
Where the three-body problem is solved
Where the microwaves play
Down at 3 degrees K
And the cold virus never evolved.
To-do List: Receive telemarketing call during a tornado warning. Check.
Yes, it is true that the International Space Station has taken a horrendous amount of money that could've been spent on real science. I admit that I'd like to see more money spent on real science missions like probes to Pluto or Europa or on more Space-based telescopes, but unfortunately as these devices increase in size (satellites, space telescopes, probes, etc.) it becomes infeasible to launch them in a confined shuttle (I believe Chandra X-ray telescope reached the volume limits on what could be launched in one piece).
That said, we need to be building an infrastructure for launching larger and more complex devices into space. This requires places where things can be assembled once in orbit, places such as the ISS or another station at a Lagrangian point. In and of themselves, these stations aren't spectacular, they don't produce good science and they are very expensive, but they need to be created to assist other scientific endeavors as our technology continues to develop. As an example, routers, fiber, and transcontinental backbones are expensive and to the layman, they produce no real science or pretty pictures, but they are necessary as an infrastructure over which people can do some really cool things.
Anyway, I think that even if this doesn't get passed by congress or the things run behind schedule, it is good that we are at least PLANNING to do some really cool stuff like this.
I drink to prepare for a fight; tonight I'm very prepared. -Soda Popinksi
This!
If you don't want to repeat the past, stop living in it.
now that you have publicised the radiation risk, there is no way that Nsync singer will go into space ... and there dies our last chance of getting him sterilised and stopping him from having offspring ...
I've long felt that human progress into space has been on some form of hold since the 1960s. JFK announced that we would goto the moon not many years before we actually did. Then we went back a couple of times. Then not much.
The major achievement of the late 70s was the Space Shuttle. The major achievement of the turn of the century will be the ISS. Obviously these are significant achievements but why we haven't been back to the moon in 40 years is baffling.
I'm very happy to see a station being considered that won't just be in orbit. I hope it is a sign of things to come. I'd really like to see a moon base in my lifetime. I don't know much about space but I'd expect it must be easier to build a big station if you build it on something.
We need to be up there. In large numbers. We need private industry up there. NASA should be focussing on putting human living quarters in space and providing transportation up there. I think there should be some kind of space oriented general contracting agency focussing on getting as many people up there for as long as possible. We need scientists, professors, entrepeneurs, the media...all sorts of people to go up and see what we can make of it.
If space really is the new frontier, it should be accesible. I hope this is a step in the right direction.
I thought Lagrange points collected a lot of dust, which would be bad for optics. Its not like you can vacuum that stuff up either. If you are 5/6ths of the way to the moon already, why not just go the rest of the way? A luna's gravity keeps the dust down and provides many other benefits. I expect Luna would also supply SOME building materials, like maybe 10 foot thick rock walls to stop cosmic rays, for example. The lunar gravity would be a disadvantage for launching other missions from there, but perhaps that could be compensated for.
If there are more informed people out there who see what I don't, I'd love to hear it.
Don't moderate flamebait as Troll. Know the difference or you will be Meta-moderated.
Fair question, but one with a fairly simple answer. Lets do some numbers...
To within a factor of a few, what matters in radiation shielding is "surface density", i.e. how many grams of material per square centimeter there are in your shield. So you can have a thick shield of light material, or a thin shield of dense material; for the same area they will provide the same shielding effect if they have the same mass.
Say for a moment that you want as much shielding as provided by the Earths atmosphere; that works out to be about 10 tons/square meter. (If you SCUBA dive: remember that the pressure goes up by 1 atmosphere for every 10 meters of depth. A 10x 1x1 meter column of water weighs 10 tons.) Those ten tons/m2 can be in any form you want: a 10 km thick air shield, 10 meters of ice, 2 meters of rock, or a meter of lead.
So, you want to put a couple of guys in a spaceship and send them to Mars? Well, put them in a cramped tube, say 10 meters long and 3 meters in diameter. That gives you about 100 square meters of surface area.... or 1000 tons of shielding.
At current prices it costs about $20,000 to put a kilogram of material into low Earth orbit. The biggest rocket flown to date can put about 100 tons into orbit. With current technology you either hit up Bill Gates for the 20 billion, or you can skimp on the shielding. The space station skimps by a factor of 300 (you get a years ' worth of background radiation in a single day). You could also play games like have most of the spacecraft lightly shielded, but have a lead-lined "storm shelter" for the times when solar flares erupt. This works because much of the radiation comes in bursts. However, it isn't useful for going to places with continuous high levels of radiation, like Jupiter.
That's why we need a new and cheaper space launch system.
Human genome = 3 billion base pairs = 6 GBit. Windows + Office = 20 Gbit. Which is more impressive?
Not to be picky, but this is Slashdot. Picky is what we do here. The rocket for the lunar Apollo missions was the Saturn V series booster, not the Apollo V.
The Saturn series was used after the Lunar Apollo four times (correct me if I'm wrong). Three were Apollo CSMs (one to ASTP, two to Skylab), and one, a Saturn INT-21 (a modified Saturn V) boosted Skylab, which really was a good scientific experiment, to orbit.
-twb
Many here have spoken of the "insane" "horrendous" "crazy" amounts of money spent on IIS. How many think that this money was spent *mostly* to make sure that no one died?
.005% of risk reduction? Unwise, because we lose the ability to pursue our dreams. We're deadlocked.
Was it a good thing to spend that money on? Is the IIS over-engineered in favour of preventing un unfortunate death? (Aside - How many of you, after viewing the interior of an Apollo era craft, would still go into space in one of those?)
Let's look at a little history. If during the 18th century, we had spent an equivalent amount of dough on sailing ships (with the (un)stated goal of preventing deaths (monarchs HATE to look bad)) I think we'd still be looking for our assholes with a mirror. We'd never have left Europe. The economy of the day would not have tolerated it.
My father-in-law was one of the Canadians who helped develop the nuclear power station system called CANDU. His stories are quite telling. His take on risk? - during development of CANDU the engineering studies required would fill a couple of banker's boxes. Today, those studies would fill a small stadium. With a exponential rise in cost. Why? What's the return? A couple of lives? A dozen lives?
My point is - we have tried to reduce the risk to zero and this is not only stupid, but unwise. Stupid because there will always be a risk. How much money are we going to let timid politicians/bureaucrats spend on that last
"Acceptable risk" is a term that has been lost from the West's vocabulary and it is time to bring it back.
Stoptional
L1 is about 5/6 of the way to the moon, along a direct line from the earth to the moon.
L2 is opposite the L1, over the far side of the moon from the earth.
L3 is close to the moon's orbit around the earth, but on the opposite side of the earth from the moon.
L4 and L5 are also in the orbit of the moon around the earth, but one is 60 degrees ahead of the moon in its orbit and the other is 60 degrees behind.
You can find more information at this web site and there is even more detailed information to be found here
Sapere aude!
My take on the subject is that we don't have any materials heavy/stable enough to reflect high energy radiation.
The problem is that conventional materials of all types misbehave as photon energy substantially exceeds the chemical binding energies. You go from having materials acting like ideal classical conductors or dielectrics interacting with photons that act more or less like classical EM waves [normal reflection and transmission], to having materials that act like a set of quantum energy levels and photons that act like particles [photoelectric effect], to having materials that act like a diffuse sea of particles that scatter photons which also behave like particles [Compton scattering].
As the valence shell binding energies in atoms are at most on the order of a few tens of eV, there is a hard upper limit on the frequency of radiation that conventional optical elements made of normal matter can handle.
The limit's mushy in one respect, in that grazing-incidence devices see an effective frequency that's inversely proportional to the angle of incidence. However, practical devices limit the benefit of this to between a factor of 10 and a factor of 100 (so you can see some x-rays, but gamma rays are still tricky).
Non-conventional optics made of normal matter can still work under some conditions. Because the inter-atomic spacings in crystals are in the same ballpark as high-energy photon wavelengths, you can get diffraction occurring when an x- or gamma-ray beam passes through a crystal (due to scattering off of inner-shell electrons and the nuclei). This is commonly used to identify materials (x-ray diffraction patterns have been used to image atoms in everything up to and including crystals of viruses). Gamma ray telescopes using crystalline blocks to construct diffractive optics have been built.
Lastly, the final and most difficult way to cheat involves using plasma as a mirror. As it's a gas of free ions, it should have near-perfect reflection even at high wavelengths (subject to a few probably-nontrivial conditions). Keeping a cloud of ions confined to an optically flat surface is left as an exercise for the reader.
While maintaining position at L1 is technically more challenging than maintaining position at L4 or L5, it has a higher payoff. For one, you won't be trying to build your space station in a veritable gravel pit in space. Secondly, it's trivial to launch vehicles from the point - you just let them go and they'll drift off without active station keeping. And considering how the intended primary purpose would be as a place to launch other missions from, that's a slightly useful thing.
If it's really so hard to put things at L1 and keep them there, you better go tell the SOHO team who have successfully kept that satellite at the Sun-Earth L1 point for almost 7 years now, without ever being "headed for Pluto".
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
GiliadGreene has made some good points already about SOHO being in a halo orbit around the L1, not at the actual L1 "point".
Orbit corrections are performed every 17 weeks (four months, not one).
The halo orbit is much saner than trying to stay at the L1 point, and it attenuates solar interference. Ironically, the COMSAT link that DSN uses to get data from Madrid to California gets more solar interference than the spacecraft to ground link.
I hold it, that a little rebellion, now and then, is a good thing. -- Thomas Jefferson