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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.'"
Actually, it just seems large because the moon looks so small. My guess is you're holding the telescope the wrong way round.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
I can't believe it! Do you? *gasps*
http://www.object404.com
...n unbelievably large telescope on the moon.
Any technology distinguishable from magic is insufficiently advanced.
As with many ideas, this is so simple I can't believe we haven't thought of this before.
'Impossible' is a word that humans use far too often. -- Seven of Nine
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.
Yeah, building stuff on the moon is a doddle.
Hmmm...as the article notes, the idea of liquid mirror telescopes isn't new, so it seems a tad odd that this is being trumpeted as a breakthrough.
The ionic liquid coated with silver is cool, though.
Kythe
Since the "dark" side of the moon is protected from the radio emissions from Earth, I think it's inevitable that the dark side will one day be "the" spot for big radio telescope arrays. Why not put our biggest optical telescope there as well?
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
You just build a big tube. Like a giant internet that goes to the moon.
Maybe not
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.
VLC FOR MAC IS DYING! IF YOU DEVELOP, PLEASE SAVE IT!!
This is total lunacy!
Knowledge is power. Knowledge shared is power lost.
Really? I wonder what they did wrong. Maybe they should have just bought plane tickets to Canada instead:
http://www.astro.ubc.ca/LMT/lzt/index.html
it wasn't even part of a myth, it was part of a contest between two outside groups trying to start things on fire with mirrors. when they discovered that all teams were technically not fully within the rules they had to revise their mirrors, the one time tried to use plaster in a spinning platform to form parabola but it didn't come out with the correct shape so they had to abandon it. no myth was busted from this.
it was this episode
I know this isn't typical slashdottiness, but I actually read the article, and have some knowledge of telescopes in general. But since you won't believe me purely on my supposed knowledge, here's a quote from TFA:
And to add insult to injury (Uh Oh...): http://en.wikipedia.org/wiki/Large_Zenith_Telescope
Yeah... They'll never work. Mythbusters said so.
Coz eternity my friend, is a long *ing time.
It would mean having to choose the right material (solid at moon temperature, liquid at not too much more, small/no surface crystals on freezing, ionic so that it can be coated with silver, ...). Making something like this on the moon would be much cheaper than taking it up there.
OK: I understand that they might not want to steer if far off vertical to keep things cheap but I would have thought that a little directionality would be a boon.
If this would have been a "steampunk" telescope on the moon, then this article would have made boingboing.
One hopes they have better things to do. Do you Slashdotters even read articles?
Some people who actually know what they are doing tried it and it did work.
BTW the first working laboratory LMT was built in 1872.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
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!
This could be the key to making a giant lunar observatory
Or a fully functional battle-station.
A lot.
The mass of the moon is ~7*10^22 kg (70 billion trillion kg). The mass of the Saturn V rocket is about 3 million kg. If we sent up a Saturn V rocket for every man, woman, and child on the planet, we wouldn't even be close to an appreciable fraction of a percent of the moon's mass. And even if we were, it is a stable system so there wouldn't be any significant effect.
Look, I don't care who you work for sonny, you are not flying with more than 100ml of liquid in your luggage, so hand it over. Bloody astronauts think they are so superior.
Home fucking is killing prostitution.
...at the sun's gravitational focus. You'd be able to resolve a planet halfway across the galaxy.
First link I pulled from Google (but there are several others): http://www.centauri-dreams.org/?p=176
As I understand it, the moon's gravitational pull works against the earth's and the two are in a sort of balance that determines the distance of the moon's orbit, or something.
Yes, but the mass of the object is irrelevant. Very approximately, an orbit is where the outward force due to centrifugal force[*] is equal to the inward force due to gravity; both these terms scale linearly with mass, so if you increase the mass of one, the other increases proportionately and the balance remains.
(This is why the space shuttle and the space station can be in the same orbit a few metres apart, despite being different sizes.)
Also, in general the human race is nowhere near able to do any kind of cosmic engineering, deliberate or otherwise. Even if we bent all our resources to it, we wouldn't even be able to significantly resculpt the surface of our own planet, let alone another one.
[*] To pedants: yes, I know.
(BTW, the moon already is lopsided. The same tides that pull water around on Earth pulls the rock around on the moon. The near side of the moon is significantly larger than the far side. Interesting factoid: the moon is so irregular that setting up a stable orbit around it is really hard.)
Everyone, sing with me:
We're whalers on the moon
We carry a harpoon
But there ain't no whales
So we tell tall tales
And sing a whaling tune
Oh yeah? What about the the Pioneer and Voyager probes that we've sent (almost) out of the solar system!?
Relax. The amount of mass is too small to make a real difference. The December 2004 earthquake that caused the Indonesian tsunami released more energy than we've ever produced/harnessed as a race, and consequently moved many orders of magnitude more mass than we will in the foreseeable future. Its effect on Earth's rotation was the barest fraction of a percent.
How in the world will they protect the device from micro & macro impacts?
Don't make big plans, 'cause you're broke...
You can't have a trillion dollar bailout of the rich bankers, buy up every dishwasher's quarter-million dollar underwater mortgage, hold a permanent-endless war on the other side of the world, ... and have a giant telescope on the moon. It's not possible, it's science fiction.
All the space exploration projects being talked about and planned for the 2020's may actually happen...in the 2120's or 2220's. Not in ten years from now.
I know that you're all young and starry-eyed, but in the bankrupt USA, reality rules. And reality says that there isn't going to any giant new space program in the 2010's-2020's.
Don't just mod me to -1 for simply telling you the truth. And don't tell me how small the giant new space program is compared to other absurd federal government programs. Those programs are toast also.
My American friends...you are simply broke... you have dreams... but you have no money.
vatch me split my letters.