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New Method Discovered For Making Telescopes On the Moon
NASA scientists have discovered a way to craft very large mirrors using carbon nanotubes, some epoxy, a little bit of aluminum, and large quantities of lunar dust. They say the technique will allow the construction of massive telescopes on the moon without the expense and risk of transporting the mirrors from Earth. Douglas Rabin of the Goddard Space Flight Center is quoted saying, "Our method could be scaled-up on the moon, using the ubiquitous lunar dust, to create giant telescope mirrors up to 50 meters in diameter." While this breakthrough was relatively cheap, NASA is currently offering up to $10 million for other good lunar research projects.
so .. after the mirrors are finished. how do they propose to keep the mirrors dustfree ?
using carbon nanotubes, some epoxy, a little bit of aluminum, and large quantities of lunar dust Is there anything he can't do?
Forget your stupid observatory! I'm gonna make my own! With hookers! And blackjack! In fact, forget the observatory!
Taking away good American mirror grinding jobs and sending them to the moon (probably to be made by illegal aliens) while depriving FedEx of the shipping revenue!
Somebody contact Lou Dobbs!
...cannot wait to see some mad scientist use this technology to turn the moon into one giant magnifying mirror and having a nice game of "ants on the sidewalk." (And of course, the obligatory welcome to our new super-reflective overlords. Sigh.)
Took this comment seriously, did you?
Heck, the first thing that came to my mind was "When did NASA hire MacGyver?" :-) Anyway, the process sounds quite reasonable. And Moon would make a wonderful observatory. I have been dreaming about lunar observatories since I was a kid quarter a century ago (at that time, I stumbled upon books written by a well-known local popular science writer).
No atmosphere, sixth the gravity, little need for compensating the structure deformations? Sounds good. The question is how heavy the manufacturing equipment would be. And there might more problems at least with optical telescopers - I recently stumbled upon a nice article on this topic.
Ezekiel 23:20
It takes forever to count out 6857 grains of salt as well. I suspect they'll just write down "one cup of nanotubes" and be done with it.
Took this comment seriously, did you?
How cool would it be to design and build huge projects in 1/6 gravity? There would have to be some incredible designs that would just be too fragile to stand up under Earth atmosphere and gravity, and the range of materials you could use would seem limitless. Maybe a nest of lasers to give a long-term boost to an interstellar probe?
There's got to be huge advantages to building in a lunar environment, with raw materials available right there, and the chance to create living space just by drilling and sealing instead of fabricating from scratch.
I've calculated my velocity with such exquisite precision that I have no idea where I am.
We're whalers on the moon
We carry a harpoon
But their ain't no whales so we tell tall tales
And sing this whaling tune
Brett
"That's no space station. It's a moon!"
Getting a large enough volume at room temperature (assuming you need some air pressure too) on the moon to mix it with epoxy and spin it (also presumably at room temperature) might be pretty hard to do without some bulky equipment. Although vacuum coating the mirror blank might seem easier on the moon, as other commentors noted, how do you keep it dust free?
So to summarize...
1. Bring epoxy, carbon nanotubes, aluminum and big spinner to the moon
2. ???
3. Coat resulting lunar dust blank with aluminum to make a mirror
4. Profit?!? (until it's covered with dust)
Aluminum is a form of Aluminium found only in North America.
We are all just people.
Not really.
they'll prolly mix it up and end up exploding.
Astronomical telescope mirror manufacturing is a labor intensive, hands-on, non-automated process. And the culture of aerospace is highly risk averse: this comes from the very customers, like the good people at NASA Goddard.
:)
Lunar telescope manufacturing would require some exciting scientific, engineer, and processing improvements that would also pay off for terrestrial manufacturing.
First, assuming they're not planning to house and employ a standard aerospace company, with 1000 engineers, technicians, and managers on the moon, this would be fully automated. Mirror making is anything but automated. The development of highly automated methods for processing and testing mirrors would be quite a move forward. It would also have direct benefits for conventional manufacturing.
Second, making a mirror on the moon would seem to require a tolerance of risk currently not accepted. Every time a mirror is moved, a crew of people must oversee the affair, sign the (physical) paperwork, and manually inspect the mirror afterwards. For lunar construction, this would have to become an assembly line that ran without that direct oversight, paperwork, or crews. Enabling more efficient methods would certainly benefit normal processes as well.
Moreover, the task of creating such a facility would keep many, many aerospace workers employed for years
ShoutingMan.com
More accurately, it would appear to be the first time that we (humans) have manufactured something off-planet with native resources. As noted, we've used extra-terrestrial materials before in the form of meteor/asteroid material. It *is* pretty exciting, if just for the proof-of-concept that we can "live off the land" (so to speak) off-world.
So, Ikea has an astronomy equipment division?
Yes, their biggest seller is called Skope, but you can also get the Refraktor or Kassegrain.
When our name is on the back of your car, we're behind you all the way!
I see your informative link, and raise you a pithy comment.
Sorry for posting as AC, I've been a lurker on these boards for too long.
http://www.sciencefriday.com/newsbriefs/read/113
Anyways, a professor in my physics departement, Ermanno Borra, has been working on a very similar concept for about 20 years. And honestly, it has become pretty much a running joke, seeing how much money he's getting from the government, although he has very few results to show.
He works on liquid mirrors. It uses a liquid that is preferably ferromagnetic and covered with a thin film of silver nanoparticles, so that you can put an array of electromagnets under the spinning mirror to do real-time spatially-continuous adaptive optics. Sounds cool (which it is), but there are a lot of difficulties that come to mind which are presumably common to the project described in TFA.
Firstly, the parabolic shape is always pointing up. Since the mirror is liquid, as soon as you tilt it to the side, it loses its parabolic shape, and becomes useless. Now, the adaptive optics part may help you to try to correct for the distortion, but the best results that Borra managed to get is a correction of a tilting of about a tenth of a minute. Disregard this if the material they use for spinning actually solidifies after a while - you could tilt it afterwards, I guess. Not the liquid one, though Borra has promised a range of 5 to 10 degrees on his device for years.
Even if it becomes hard as concrete, the logistics of tilting a 50-meter wide piece of concrete without any structural deformation is impressive. That means, unless you find a way around this, you'll have to keep your mirror looking up, at all times. So you either place it on the pole, in which case it will be looking at the same place for a very, very long time (until precession slowly moves it around). This is good for doing very deep fields, but hasn't much use otherwise since if there's nothing interesting to look at there, you're stuck there anyways.
Or you can place it anywhere else than the pole, but then you're never gonna look at a given object for more than a couple seconds.
Just reading TFA and thinking that, after reading the sentence "When they mixed small amounts of carbon nanotubes and epoxies (glue-like materials) with crushed rock that has the same composition and grain size as lunar dust, they discovered to their surprise that they had created a very strong material with the consistency of concrete.", wouldn't building living (and other) structures on the moon using this material be a better application of this technology?
myke
Mimetics Inc. Twitter
Size, availability of materials to construct it out of, and, as TFA pointed out, a stable platform to work from.