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Unbelievably Large Telescopes On the Moon?
Matt_dk writes "A team of internationally renowned astronomers and opticians may have found a way to make "unbelievably large" telescopes on the Moon.
'It's so simple,' says Ermanno F. Borra, physics professor at the Optics Laboratory of Laval University in Quebec, Canada. 'Isaac Newton knew that any liquid, if put into a shallow container and set spinning, naturally assumes a parabolic shape, the same shape needed by a telescope mirror to bring starlight to a focus. This could be the key to making a giant lunar observatory.'"
When I saw the summary I actually HOPED it would be misleading, because it makes it sound like nobody had thought of liquid mirror telescopes before. Now it's possible that they were just copying a similarly misleading article, but no... even has a nice photo of the Large Zenith Telescope to spice things up. Space Fellowship 1 - Slashdot 0.
I think the break through is the part where they build it on the moon. I understand how building a massive telescope on the moon will be difficult, and although this may be slightly easier, I don't consider it a massive breakthrough.
I would consider a massive breakthrough building the telescope out of moon dust, or some other material readily available on the moon. That way, we don't have to transport massive amounts of equipment to the dark side of the moon.
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
The biggest issue I see with this tech on the moon is that not many substances exist as a liquid in a vacuum, and while I appreciate that the lunar surface isn't a true vacuum, it's good enough that your telescope would either evaporate or freeze almost immediately.
That said, if you could get a liquid mirror up there and spin it into shape, you could then expose it to the outside temperature to freeze it, and you'd remove the need to keep spinning it forever.
couldn't possibly be a lid on it to protect it from lunar dust/solar winds/micrometeorites. No possible way they'd think of that. Absolutely implausible that they'd use a static charge to repel ionized particles either, just fucking inconceivable.
Um, how will it transmit images back to earth, with the entire moon blocking radio transmissions?
The "liquids" to be used are less dense than water, and being placed on the lunar surface, which is covered in dust several times finer than baking powder.
I'd give it about 3-5 days (depending on the size) before the "revolving liquid mirrors" become revolving lunar mud pies.
How? Is the wind is going to blow the dust onto the mirror??
we don't have to transport massive amounts of equipment to the dark side of the moon.
It's FAR SIDE people! Far Side, Far Side, Far Side. Like the cartoon. The Moon is tidally locked to Earth, so there's a Near side and a Far Side. If it were tidally locked to the Sun, then you'd have a light side and a dark side. But it's not, so we don't. There is no dark side of the moon, except for the ever changing half that's facing away from the sun at the moment.
When our name is on the back of your car, we're behind you all the way!
Splitting comments...
... between subject and body is bad.
Splitting wo...
...rds is even worse.
Why do you people do it??? (Serious question)
At the risk of sounding adolescent: LOL, BURNED!!
Now, with that out of my system, I must admit that I find it incredibly comical how much some people rely on MythBusters for their info. Don't get me wrong, it's a good show, but seriously, for things like this, they act as if these same two guys can prove or disprove ANYTHING within a day or two of playing around with it.
Fusion research? Why bother? Call the Mythbusters and they'll let us know by next week whether or not it's feasible . . .
"People who think they know everything are very annoying to those of us who do."-Mark Twain
In order for the 'mirror' to maintain its shape it would have to be continuously spinning during the 'freezing' phase. If it were to stop and 'settle' you would end up with a useless, slightly convex, mirror. Also, whether you find the materials necessary to manufacture the mirror on the Moon or not, the machinery to produce the mirror and the rest of the observatory need to be sent from Earth, first, which makes this a totally unfeasible, insanely expensive. proposal.
Smart science type guys do it again. "Hey, we can make 'X' for really cheap on the Moon. The only problem is that we have to get to the Moon to make it really cheap."
Sig this!
How in the world will they protect the device from micro & macro impacts?
You might want to read up on how fast that happens.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Funding for universal health care has to come from somewhere. If not new taxes, other programs are going to take a hit. Unless people lobby for continued space exploration, programs like this are easy targets. What many /. folks may find as important may not hold true for those with political influence.