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Telescope Will Have Images 10X Sharper Than Hubble
jangobongo writes "After a 20 year struggle, the University of Arizona's $120 million Large Binocular Telescope was dedicated last week. This unique telescope will have twin 8.4-meter (27.6 foot) mirrors that sit on a single mount. Using methods similar to a medical CAT scan, a technique of "tomographic" image reconstruction will be used to produce pictures 10 times sharper (example) than the Hubble Space Telescope for a fraction of its $2 billion dollar cost."
I don't really think it's fair to compare this with the hubble, unless this telescope can orbit earth.
The "example" image shows the upper left corner as "Seeing Limited", but it's not clear what that means. Not the human eye, obviously? Anybody know?
Weeks of coding saves hours of planning.
Here is a particularly good description of the LBT (Large Binocular Telescope) from an article in the Eastern Arizona Courier.
The LBT is made up of two 8.4-meter mirrors, which, when in place, will bring together the light, creating sharper images of faint objects in space. One mirror is in place at the Mount Graham International Observatory, and the other will arrive next spring. Each mirror is designed in a manner that allows it to reach the same temperature as the outside air up to two hours faster than any other mirror design. Under the solid glass surface are openings in a honeycomb pattern. Cold air is pushed up through those openings, cooling the glass to the desired temperature. The sooner the glass cools, the more science can get done, which is good from a business standpoint, assistant project director for LBT Jim Slagle said.
Not everbody is happy about this, though. The Apache people are protesting the use of the site for the telescope.
The U of A is finally dedicating it's Large Binocular Telescope (LBT), formerly called the Columbus Project, after years legal and money problems and at least a year before actual completion. (The U of A changed the name of the project after realizing it wasn't such a popular idea to name it the Columbus project and then, against the wills of the Apache people, place it on their most sacred site on top of the mountain.) The LBT is mainstay of the project. Investors will be wined and dined on Fri. at the La Paloma resort in the Catalina foothills and bused up to the mountain on Sat. to tour the scope site. Our job is to show the investors how controversial and unpopular this project is... and has been for decades.
http://www.busyweather.com/
Because to build a space based telescope costs a lot more money than a ground based one. Not to mention launch and maintenance costs associated with something like hubble.
*cough*$10 billion*cough*
As amazing as Hubble has been, I fail to see how dumping huge sums of money into keeping it going is worth it if we can dump similar sums of money into earth-based technology with better results.
-S
--- What parts of "shall make no law", "shall not be infringed", and "shall not be violated" don't you understand?
A space-based telescope (like the Hubble) can be rotated and aimed at almost any object out there. In that sense, a Hubble is still superior in some aspects.
On the other hand, just the fact that adaptive optics and interferometry can clean up the images so spectacularly is simply amazing!
I wonder how long before I can get a consumer-grade version, to take pictures of the coeds^H^H^H^H <ahem> natural "scenery"... ;-)
But what about the frequencies sucked up by our atmosphere? These wavelengths are pretty cool to stare at, right?
A NYC lawyer blogs. http://www.chuangblog.com/
Pardon me for asking, but isn't atmospheric interference still a factor for ground-based observatories? Won't this affect their observations?
Granted, the telescope's location is a plus in this department (there are few locations more suitable) but the potential interference is still a consideration. I've read their page on ground versus space telescopes and it touches on this issue, talking about fast computers and adaptive optics that correct atmospheric blurring, but it's not an issue for which you can completely compensate.
Having said that, a ground-based observatory is a heck of a lot cheaper than an orbital one...
"Accept that some days you are the pigeon, and some days you are the statue." - David Brent, Wernham Hogg
Earth-based telescopes have their role too. So it should never be either or. For example, a lot of the planet detection has been done with comparitively weak earth-based telescopes. So if telescopes like this become more commonplace, there is a large benefit.
That being said, if you could use the same technique from space and not have to worry about atmospheric distortion, dispersion, and absorbtion, you could potentially do some really cool things.
LedgerSMB: Open source Accounting/ERP
Slightly OT and perhaps a stupid question, but I always asked myself if hubble was turned against earth, would that give you the possibility to get a very detailed image (assuming no clouds)? Anyone here who knows why or why not at all?
Dude, if you can build another Hubble for $10 million, you're a miracle worker.
Hell, if you can LAUNCH another Hubble for $10 million...
Cripes, even launch the frickin' MIRROR for $10 million...
How about a box lunch for one of the workers? If you could launch THAT for $10 million, that'd put you into major miracle worker status.
> This isn't intended to be a troll, but I just don't get space exploration. I mean, there are a lot of good causes that all these dollars could be going to right here on Earth: stopping wars, battling diseases, increasing literacy, fighting pollution.
Better yet, why not use the money we spend on wars for all that good stuff, and maybe we'll have enough left to do some space exploration anyway.
Sheesh, evil *and* a jerk. -- Jade
"theres not air in space..."
But there's an Air in Space Museum?
Unknown host pong.
Sadly, I'm not qualified for any of them.
Win a signed Stephen Carpenter ESP Guitar from the Deftones: http://def-tag.com/?r=0008781
I spy, with my $120m eye...
something black and vacuous!
It's only a model.
The story gives the impression that the LBT will completely replace Hubble, and do a better job, while being vastly cheaper.
This is an overstatement. There is lots that Hubble can do that no other telescope can, being a unique combination of aperature (light gathering power and resolution), instruments (many wavelengths, imaging and spectroscopic) and being above the atmosphere (no 'seeing', no atmospheric absorption or emission in UV and IR.)
(This is not to downplay the LBT - doing better than HST in some aspects, and as well but much cheaper in others, is very valuable.)
Having quickly scanned the website for this telescope, I can't see how they are counteracting the bluring of 'seeing' (atmospheric turbulance). It is inconceivable that they have neglected it, but I don't see where. Adaptive optics can help, but have limitations of their own.
Another limitation of the LBT is that the high resolution reconstruction will require 3 observations at different times - so it only works well with non-time-varying targets. This is a minor limitation, however - a large majority of targets for which you want high resolution are non-variable.
(IWAA: I was an astonomer. PhD, but no further.)
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
It will permit formation of images of sufficient sharpness (diffraction-limited) that the planet could be detected against only a low surface brightness halo of residual scattered light. In this manner, a Jupiter-like planet could be detected, if present, around some fifty of the nearest stars. The interferometric mode will enhance the planet/background contrast even further, thus increasing the number of candidate stars and the sensitivity of the survey. The direct detection of such a planet would surely be counted as one of the major steps forward in determining the likelihood of life existing elsewhere in the Universe and in understanding our place in it.
So, gas giants, but no mention of anything Earth-like. Too bad. I'd definitely be psyched to someday hear about "Earth-sized planet discovered about an AU away from a Sun-sized star."
You could probably get the lunchbox to an orbit similar to Hubble for about $15M. Launches on Eurockot look pretty inexpensive, and China might be competitive, too. If you're lucky you might get the lunchbox to a decent orbit for almost nothing as a secondary payload on someone elses launch. It'd probably still cost more than $10M in management and paperwork in addition to the launch cost. There ain't no such thing as a free launch...
Actually I think you are missing something... NASA was is space in the 60's. Private enterprise only made it in '04 because someone was willing to throw a lot of money at a prize. In fact NASA works with private enterprise on almost everything it does,,, it just happens to be very expensive doing it first.
but as an astronomer,
/me ducks
so, you took up space in college eh?
"goodbye and hello, as always" ~Prince Corwin, from Zelazny's Amber series
BEside the fact that it's a state university, This proves nothing. Hubble was built years ago. How much would it have cost to build this telescope when Hubble was built? I don't think it was even possible then.
The Kruger Dunning explains most post on
First, all "these dollars" are spent right here on earth anyway. The idea that somehow or other money spent on research for space or technology is gone when the space craft is launched seems to be a common fallacy. It is also a faovorite that is often promulgated by parties with an interest in keeping frontiers closed and humanity in bulk pig-ignorant (religious zealots, some political parties, etc.).
Second, I doubt that any amount of spending will "stop" a war. Wars are inherently economic at root. A Cheney or a bin Laden or a Bush, a Haliburton or an Enron is always, always in the background with an "interest" in the objective of any conflict. Ideals and religious rationalizations are used by all sides in a war, but curiously, neither the idealists nor the religious seem to supply more than cannon fodder. The commonest example of this these days are the leaders of Muslim terrortist groups. You don't see THEM with a pound of semtex strapped to their bodies, or out taking lessons in crashing airliners. Nope, its some poor sap with a burning desire to purify the land for his religion or to get even for a real or imagined harm done by some equyally misguided zealot on the other side. What would stop wars is for the "followers" to hand their leaders the bag and say, "O.K. boss, your turn."
------ The only greater hazard to your liberty than n politicians is n+1 politicians.
The radius of the earth is about 6400 km, and hubble only orbits about about 570 km above that. If you do the trig, hubble only has a 225 deg feild of view at any one time compared to 180 on the earth (disregarding the atmosphere in both cases).
Furthermore, both hubble and an earth bound telescop would have a somewhat limited view due to their "orbit". Concider a telescope on the equator. It would have a 180 degree field of view at any given time, and over the course of a day, everything would be in it's field of view except a cylinder the width of the earth, centering around the earths rotational axis, and extending to infinity in either direction. If you have telescope further north, it's daily field of view would have a cone shaped blind spot to the south. Hubbles orbital blind spot would be nearly non-existant over its orbit period, slightly better than the observatory at the equator, but that is easily solved by having two observatories - one in each hemisphere.
Concidering how inexpensive these are to build relative to a space based telescope, there is no reason why we can't do this. In fact we have hundreds of observatories across the world, each new or improved one slightly better than the one befores, but only one space based telescope. Improvements in ground telescopes will also be available to many more researchers, than with just one expensive space telescope.
Years ago, people did not "get" technologies like the computer. I mean, what good was an unreliable, hugely expensive machine that took up a rather large room? Who would want buy one, and for what purpose could they use it for? But look at where we are now, some 60 years after the first computer. Even if you can't think of any good that will come out of space exploration, just remember you do things everyday with computers that no one even imagined 50 years ago in their wildest dreams.
I have seen several stories of telescopes that promise equal-or-better than hubble images. Usually there are some drawbacks. Here are some of the drawbacks that came up:
1. Limited range of sky
2. Frequencies different than hubble, such as only infrared.
3. Only works near bright stars due to "guide-star" anti-blur technology.
Let's see if new techniques get around these.
Table-ized A.I.
You might point out to your friend that the optimum angular resolution of the HST is about 0.1 arcsecond. That represents the angular size of a 600-foot object 238,000 miles away...which means that if the Pentagon and Buckingham Palace were on the moon, the HST would be able to see one and not the other.
rj
wakeup, look around for bifocal specs, life is pretty fuzzy at this point, no discernable features but you know there's something "out there"
put specs on, at least the various colored blobs have a certain vague meaning to them now
stumble to john, return, grab a coffee, head to mess...er, "desk in office-like area",human engine is warming up,optical sensors are starting to register in real time, although steroscopic vision is still askew
sit down in front of box, stare at screensaver as it slowly revolves around random patterns, then nudge the mouse, official "day" begins....ahh, all is well...still fuzzy and confusing, but now it's in a sort of focus-mode
Meh. We spent $80 billion to go kill people (erm, I mean get oil. oh I mean liberate the people! that's it!) in Iraq... what's $10 billion to help people understand the Universe?
:-]
With politicians running the government we're all fucked
My other car is first.
Heck. we could even build a whole telescope _array_ on the moon... just imagine what we would be able to do with that!
File under 'M' for 'Manic ranting'
While this telescope may have even better resolution power than Hubble, there's another major problem with all ground-based telescopes
They cannot detect EM waves that's not either visible light or in the radio wave to the far infrared range
This is because Earth's atmosphere, contrary to what most people would believe, is not transparent to EM waves of all wavelengths. For example, common sense tells us that it blocks almost all extreme UV light. So if you want to observe an object that emits only extreme UV light with a ground-based telescope, you're not gonna see it.
Another example would be gamma ray bursters. Remember these objects weren't detected until the US sent survillence satellites into space? This is because there's no way you can detect gamma rays that originated from space inside the atmosphere. Granted it's now possible to observe the after-glow of GRBs with ground-based telescopes, GRBs must still be detected from space telescopes beforehand.
The two 8.4 meter (331 inch) diameter primary mirrors are mounted with a 14.4-meter center-center separation.
Nobody's eyes are that far apart.
You're using her as bait, Master!
I am only an ameteur astronomer but wouldn't a more valid comparison be to (the slightly lesser known) Keck Telescopes on Mauna Kea? For those of you who are not familiar there are twin 10-meter telescopes on Mauna Kea, which I'd be willing to be has infinitely better seeing (read: atmospheric conditions; the light is distorted less) than New Mexico.
In addition, one can add instrumentation and the like to ground based telescopes and not really to space based onces - hence, Keck would be a much better comparison.
Finally, I don't understand why such a big deal is made of the implied revolutionary methods that are used to combine the images from each scope. If anyone knows, is this different from any other dual telescope setup?
The Hubble sensitivity is not that enhanced from being in orbit (the atmosphere doesn't absorb all that much optical light at most wavelengths). Hubble also suffers from not being that big -- it's never going to be able to detect faint surface brightness objects (e.g., diffuse nebulosity, extended galaxies, etc., if it's too faint). You need BIG telescopes like LBT for that work.
There is, however, an area of faint astronomy where Hubble is unbeatable. And that is working on concentrated or point sources. Because Hubble can point, with high stability, for extended periods, you can detect objects that are currently impossible to observe from the ground. Check out www.stsci.edu and their press releases and look for the Hubble Deep Field images. They're spectacular, and LBT won't be able to touch them.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
I've noticed something about people. Usually the people who are most likely to criticize something are the ones who are the least capable to do any better.
Hubble has produced some of the best science yet taken in space. While others complain about Hubble or NASA's achievements, nobody has been able to do any better.
The only reason that inept people like you complain is because you're not capable of reaching the level where you'd be able to see yourself fail the intended task. You can't lose the Superbowl when you can't even make it to the playoffs.
Yes, there are things that Hubble can do that no other satellites can do, but not for the reasons you listed.
Hubble is one of multiple telescopes in NASA's Great Observatories project.
There are currently three space-bound observatories for astronomy.
For instance, Spitzer meets the qualifications you gave, the difference being that it operates in the IR range, while Chandra looks at x-rays.
Hubble works in the visible range. But that's not to say that it's the only space-based visible spectrum satellite, as there's also SOHO, which points at the sun, and isn't used to point anywhere but the sun.
[I'm not an astronomer, but I work on the STEREO and VSO projects]
Build it, and they will come^Hplain.
Every space-exploration article draws this kind of post that says, "but we have more important problems here on Earth we should spend the money on."
And would spending the money spent on space actually fix these problems? No. There's enough food in the world, to take one problem, but other issues (politics) interfere with distribution.
This criticism can be reduced to the absurd very easily. In the most extreme case, should we identify the "top priority problem" and spend 100% of our resources to fix it? And then move down some list?
Of course not. That notion is absurd.
The case for space expoloration is exactly the case as for basic research of any kind. You never know what you will discover or its importance until you do it, and supporting basic capability in science and technology is always a good idea for a society. It pays off economically in lots of ways, so it doesn't even cost what it looks like on paper.
Personally, I find it gratifying to live in a culture that values studying the universe and understanding our place within it. That says something noble about humans in a world that is too often filled with the mundane and the tragic.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
The size of a telescope's primary mirror determines its lighter gathering property (LGP). The larger the primary mirror, the more light it collects and thus the more light over a period of time it collects. The Hubble only has a 2.4m (94.5") primrary mirror, the LBT has two 8.4m (331") mirrors that combined act as a single circular 11.8m (465") mirror.
The LBT therefore collects far more light per unit of time than Hubble does. For many types of imaging the LBT ought to be able to get Hubble-quality or better images in less time than it takes Hubble to get them. A four day exposure from Hubble might only take a single day on the LBT.
This however doesn't necessarily answer the question of how far the LBT can see. Hubble is in an enviable position of being extra atmospheric. It can image in parts of the spectrum that are entirely blocked out by the various gasses floating around here on Earth. Hubble is able to take those deep universe images by imaging mostly in the IR band of the spectrum. Galaxies billions upon billions of lightyears away have enormous amounts of redshift. What they originally emitted in visible light has stretched into infrared as it's traveled to reach us. The pretty images NASA releases are just that, pretty images. They're greyscale images that have been given false colors as to be more appealing to non-astronomers.
Hubble will still be able to peer deeper into space than the LBT. The LBT however will be able to image faint visual objects quicker than Hubble (in many cases) and get far better optical resolution of large cosmological structures. A small telescope on the ground might be able to see M31 (the Andromeda galaxy). Hubble might be able to see fairly large structures like globular clusters, large dust clouds, and larger groups of stars. The LBT however will be able to see even smaller structures than Hubble. With higher resolving power the LBT will be able to produce more detailed visual band images which can be combined with other images or studies (Hubble IR or UV images for example) to provide a ton of information about the structure of that galaxy. The LBT isn't designed so much to replace Hubble or anything else, simply to expand our capability to observe and study objects in the sky.
I'm a loner Dottie, a Rebel.
The best location to grind a mirror is under zero gravity. The thickness of the mirror could be substantially reduced. You have a bonus of best environment to silver the mirror because of the vacuum. Your best bet is to transport the raw materials to the orbit and start melting/grinding/polishing the mirror in space. Start your own version of telescope-in-space X Prize challenge and you'll see results in a few years.
The moon isn't that great a place to build a telescope -- it isn't as stable a platform as being in space-- things hit it and shake it, and there's dust falling all over. You also have the problem of having to land everything gently as it drops into the moon's gravity well, which ends up costing you more energy. You're also in a varying thermal and solar environment, which is hard on equipment and decreases throughput.
Heliocentric orbits (e.g. earth trailing) or the Lagrange points (cue ZZ top) are nicer, more stable environments to put your space telescope into.
Intrinsic redshifts explain the anomalous association of high-redshift QSOs with galaxies of much lower redshifts. Space expansion was demonstrated pretty conclusively by observations a few years ago IIRC - QSS theory doesn't have a problem with this. However, Occam's razor would like to talk to the practice of putting QSOs at cosmological distances when they have been demonstrated by Arp to be associated with galaxies of much, much lower redshifts.
It always amazes me that otherwise sound scientists start talking about 'belief' whenever certain concepts are mentioned (eg. evolution and big bang theory). There is no need to believe in anything - you can just take a through a telescope (or microscope) and have a look.
The real bugger is that when you let intrinsic redshifts out of the bag (ie. that you could be observing them as a phenomenon, not on the basis of a theoretical model), several popular cosmological ideas lose a lot of credibility. Fortunately, the increasing accuracy of observational evidence will inevitably revise currently accepted models.
From the article:
the LBT places fringes on each point-like portion of the image. When we combine pictures taken with these fringes at three different angles, the fringes cross and give information about the exact placement of the point of light, distinguishing other points of light close to it. It is the crossings of these fringes that allow us to reconstruct a high resolution image.
So, does this mean that video from 2 cheap webcams pointed at the same subject, can be combined to a single higher quality stream?
The Intel Intel Open Computer Vison library already uses binocular vison to track objects in 3D space. Can it be applied to this application?
The first AO systems were active by 1974 and used for astronomy (at the US Air Force Starfire range
in, umm, New Mexico) before 1980. See papers by
J Hardy et al.
-- Thus conscience does make cowards of us all - Hamlet