Skip to comments.Construction of world's largest optical telescope approved
Posted on 04/14/2013 8:36:59 PM PDT by Jyotishi
The massive Thirty Meter Telescope will be able to image objects 13 billion light years away, near the beginning of time.
Set atop Mauna Kea, the Thirty Meter Telescope will be able to observe planets outside our solar system. (Credit: Courtesy TMT Observatory Corporation)
If you love eye-popping images of space, here's welcome news: the Hawaiian Board of Land and Natural Resources has backed building what's to be the world's largest, most powerful optical telescope above the clouds atop the volcano Mauna Kea.
The Thirty Meter Telescope (TMT) will have a primary mirror of 492 segments measuring some 100 feet across, giving it the power to image objects 13 billion light years away, near the beginning of the universe.
It may also photograph planets outside our solar system with unprecedented detail.
The focus of a collaboration among scientists in California, Canada, Japan, China, and India, the instrument will have 144 times the light-collecting area of the Hubble Space Telescope and nearly 10 times that of one of the Keck telescopes.
Despite opposition from some environmentalists and native Hawaiian groups, construction of the next-generation observatory will begin in a year and is expected to cost over $1 billion. The TMT is slated to begin scientific studies in 2021.
(Excerpt) Read more at news.cnet.com ...
$1 billion, wow. but worth it i bet.
i wonder how they make the glass that large? in pieces that focus on someting like a digital camera or something?
anhyone know how the technology works?
Use Bill Gates’ and Warren Buffets’ money, not mine, to build this stupid thing.
The Thirty Meter Telescope (TMT) will have a primary mirror of 492 segments
i looked at the design spec. its not glass, but a series of highly polished mirrors that all reflect onto an electrical eye that captures the image. i cant imagine the precision it must take to make the mirrors, keep them polished in the outdoors on a mountain top a nd then achieve the precision neccesary to focus over 400 of them EXACTLY so you can look out millions of light years. really cool
If we had kept going back to the Moon and established a base we could have put a telescope or three on it.
Stupid? Really? Scared of it Rembrandt? It is modern day exploration...
It is, in a word, AMAZING!
Mauna Kea is a volcano. One eruption, telescope and $1 billion dollars gone...of course that is a better deal than any of Obama’s bailouts.
Yeah, sure, uh huh, yep.
And just what advantage and how could this top what we get from the hubble space telescope?
Mauna Kea erupted about 4,500 years ago.
It's much larger and thus has far more light-gathering capability than Hubble.
And adaptive optics techniques that constantly and automatically compensate for atmospheric distortion mow greatly reduce the advantage of optical space telescopes over ground-based ones.
The Hubble Space Telescope has a primary mirror with a with an eight foot diameter mirror. Compare this to the 100 foot mirror of this new telescope.
If they could put this telescope on the Moon just think about how far it could peer into the universe.
I imagine the process is similar to this.
Building the worlds largest telescope on U.S. soil is a "stupid thing"?
This has to rank up there in the top 100 all time ignorant comments.
No advantave someone just figured out how th scam the Gov out of a Billion dollars! We have a space station for a plat form that does not have to look through miles of atnosphere and as the Gentleman said the Hubble!
They want to laso an Asteriod when the moon is already there!
They want to put it in the /moons orbit! Well how much farther is the effin moon!
Oh by the way ISS hows those algea growing and puter chips goin!
The costliest aspect of space travel is the vehicle to break the bounds of gravity!
Send the stuff build a vehicle @ the ISS.
The Shuttle Sysytem was the ground floor of putting parts and fuel on the ISS Send two welders and plumber to build the thing and Vala! Space travel!
Hexagonal segments which are actively warped into the appropriate shape down to 10's of nanometers.
Correcting atmospheric abberations is a difficult but tractable problem.
However given the spatial extent of the TMT multiple laser guidestars will be required......also an established technology.
The flash on that will have to be gigantic!
All basic research is eventually useful, but the knowledge yield from the Space Station has been really minor when compared to Hubble and the other great telescopes.
> The flash on that will have to be gigantic!
Hey, Obama’s got the cash!
Agreed. And how does one measure “the beginning of time.” If the stars are so many light years away, please explain how that can be proved. Please, please.. I want to know. Already know, but have to hear it now, so lonely. (ha ha)
Wow, 35 times the light gathering ability of the Hale Telescope on Mt. Palomar. Anybody remember Palomar? It was the be all and end all of all ground based telescopes for 40 years. Nothing larger could be built on the ground because a larger primary mirror would crack under and/or be distorted by its own weight. Or so they said. That was before segmented mirrors and thin flexible mirrors with adaptive optics. Man, can’t wait to see the photographs this baby will be taking.
It is an international/private/public effort. I don't believe Gordon Moore considers his donations to be a "scam".
We have a space station for a plat form that does not have to look through miles of atnosphere and as the Gentleman said the Hubble!
Atmospheric correction is a very well established technology.....If you insist on a space based instrument, the James Webb telescope is sucking NASA dry at the moment and should act as a nice compliment to TMT's instruments.
The technology required is well established.....the primary glitches are: 1. the mulitplicity of nations contributing to project...each of which will want to farm the work out on a political rather than good engineering basis....2. the logistics of operation.
For instance, each of the 492 mirror segements will need to be extracted and recoated on a regular basis....and replaced in time for night time operations for which the demand will be insatiable and worth 100's of thousands of dollars per evening....the slightest loss of time on sky will be intolerable.
Very tricky operational logistics...
One of the first things I thought of was some poor slob sneezing...
I went to the Wiki page about this.
It was the usual suspects. Indians saying the mountain was sacred and tree huggers worried about a species of squirrels.
I'm sure it took awhile before all the shakedown artists could be paid.
Science marches on.
>> ...keep them polished in the outdoors on a mountain top...
> One of the first things I thought of was some poor slob sneezing...
With “vog” emanating from the active Kilauea volcano on the same island, that can happen quite easily.
One problem with the moon is the temperature extremes. During the 15 day night it falls to hundreds of degrees below zero, during the 15 earth-day day, hundreds of degrees above. The Apollo missions were performed at local lunar twilight.
The moon is actually a very bad place for a telescope. Especially a large one.
Even though there is very little atmosphere, there is a huge day-night temperature variation: +100 Celsius in the day, as low as -173 Celsius at night.
The materials of the telescope have different thermal expansion rates, and this kills the precision of the telescope.
In the right orbit, a space-based telescope can be in constant sunlight, and the satellite designers can shade whatever parts they want to get any temperature they want.
Plus, it takes much more rocket energy to land something on the surface of the moon than to put it into orbit.
A very real issue is that launching a 100 meter primary mirror, even in pieces is well beyond our current capabilities.
Modern adaptive optics can take out a lot of atmospheric distortion.
I would agree that the best environment for a telescope is to keep it in constant sunlight, but how does the HST handle going through the Earth’s shadow orbit after orbit and still get very crisp photos? It’s orbit is only about 350 miles above the Earth.
The 30m/100 foot primary mirror is divide up into 492 hexagonally-shaped pieces that are each 1.4m (4.6 feet) across. The fairings on an Atlas 5 are four and five meters in diameter which is more than large enough to carry such mirrors.
They make the primary mirror in 492 hexagonally-shaped pieces that are 1.4 meters/4.6 feet in diameter.
This is why it is called a segmented mirror reflecting telescope.
HST has very sophisticated thermal control. Of course this can be done on a larger scale, but it can’t be done for $1 billion.
Launching 492 pieces would require hundreds of launches. Probably $100 billion. Not to mention the structure that holds them all together.
Then you have the issue on on-orbit assembly, which would make the launch issue seem like child’s play and pocket change.
Next comes the issue of a spacecraft to control the telescope. More on-orbit assembly, and lots of complexity. The angular momentum of such a large spacecraft would require unprecedented slewing mechanisms.
We might be able to put a 100 meter telescope into orbit, but look for a 10 year time frame and at least $1 trillion.
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