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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."
Why don't they just spend a single sum of around $10 mil to build another Hubble, but better. The Hubble's old now, and they're spending tons of money to build better ground ones, but the ones in space have infinitely better headroom because theres not air in space...
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.
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
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?
But not everyone is proud of the achievement. Controversy has swirled around plans for the Mount Graham International Observatory since it got its start 20 years ago atop the 10,700-foot mountain. Opponents contended the observatory would cause the demise of the endangered Mount Graham red squirrel. And the San Carlos Apache Tribe said development would desecrate a sacred mountain. Environmentalists and members of the tribe filed some 40 lawsuits - eight of which ended up before a federal appeals court - but the University of Arizona prevailed. The telescope and mountain observatory, about 125 miles northeast of Tucson, also survived two major forest fires in eight years, the most recent one this summer. "It's a sad day for anyone who believes that the University of Arizona cares about ethics, biology, cultural protection and religious freedom," said longtime project foe Robin Silver, conservation chairman for the Center for Biological Diversity.
http://www.busyweather.com/
(I forgot to log in last time so I'm reposting this under my account this time... D'oh!)
You forgot Spitzer (Link), which is up there today. There have already been more than a few collaborative projects between this space telescope and Hubble.
And on the subject of space telescopes that can see places Earth-based telescopes will never be able to see because of the blocking effects of the atmosphere: Chandra (Link), which can see X-ray sources. This one is my favorite Chandra picture.
--- Journals are boring; Go to my web page instead
A requirement on all observing proposals to Hubble is that the observation can't be done by any ground based telescope. This is so we don't waste the expensive telescope time on something that can be done by the chearper telescopes. So when LBT starts operation, there may be some observations that would have been done on Hubble going to LBT instead. But certainly not all of them.
In any case, the way things are going at NASA HQ, it'll be lucky if Hubble is still operating by the time LBT starts observing with both mirrors.
I live in Safford and you guys should see this thing! Its freakin' huge, you can see it from town and for miles around, this big ol' white box up on the hill. Its awesome! Its also a win for scientists vs. environmentalists. The wackos have opposed this for years and their efforts led to the unchecked fire that almost destroyed the site this summer.
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
Not everbody is happy about this, though. The Apache people are protesting the use of the site for the telescope.
Not to sound ungrateful, but: fuck 'em. I don't have a say as to what my homeland does, so why should they?
They waffle on about "sacred ground".. quite frankly: fuck 'em. I can only hope that someday, somebody wants to dig over my grave to further the cause of science. I can call my poo sacred if I like - but that doesn't mean it is.
Yes, I think that scientific progress should not be held back - at any cost. I think that nothing is sacred in the light of science - so long as it's justifiable. If they have any complaints, those that think the site is "sacred" should be pushing for responsible use of the site and to minimise the site's effects. Outright opposition is silly. If they'd helped, they could probably have even had a say in what happened.
The only danger mankind has is that we'll never learn the secrets of the universe - or create an intelligence that can learn and understand them, and then simplify what we want to know for us - before we become extinct. In the long run, this planet is doomed anyway when the sun explodes. Nothing on earth will be "sacred" after that. So long as this planet and this sun can sustain us long enough to make the leap to other stars, humanity will be fine.
As to the rare squirrel that might be endangered: it's not like humans can't prevent killing them. Move them, leave them alone (work around them) or domesticate them for all I care - put up food in feeders and warm squirrel boxes for them to make a nest in. Given them a lifetime supply of nuts and a warm cage to snuggle up in or something.
(Never even seen a large telescope close up, but I recognise that the space sciences are the most critical and important field of study and advancement that humanity has ever touched.)
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'
One point about AO that's rarely appreciated is that the point source function (PSF) changes. The spatial resolution doesn't just improve by "factor x." A lot of the light becomes spatially concentrated, but a lot of the light remains in the "wings" of the PSF. One application I'm fond of for high spatial resolution is imaging quasar host galaxies. In quasars, the host galaxy is usually lost in the glare of the central quasar. AO helps, but not so much -- the wings of the PSF still swamp out the faint surrounding galaxy. There are tricks to play, to push the technology to do this kind of science, but cutting edge work is usually complex.
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.
Why do Earth based telescopes need "adaptive optics" to image thigns at high resolution? And why is the resolution limited?
I do some amateur video editing, and a lot of times I have to deal with VHS casette recordings that are full of static.
To remove that static, I use something called temporal filtering. You can try this yourself free with VirtualDub.
Temporal Filtering can take a still image on a cassette and completely remove the static in the image. You can take an old cartoon, and if you can find a section where the characters don't move, you can get an output image which looks as good as the original did.
Now, most video is in motion, so temporal filtering on the cheap can't yet perform miracles and doesn't work nearly as well on that... But I think some pro software can... or cresearchers are working on it anyway.
But I digress. My point is, when you look at a star through the atmosphere, it wobbles. But it doesn't change much. It's like a still image being viewed through water.
So why not just record the image, compensating for the rotation of the earth, and then average all those images together to produce a perfect image?
Also, I know that one of thsoe european mars probes gathered high res images of mars by rotating their sattelite slightly. However this only worked on one axis, because I guess the telescope could only rotate left to right and not up and down. But an earth based telescope should have no such limitation. What's preventing us from just rotating the telescope to improve the resolution of the digital camera like on the mars probes, and using the temporal filtering method instead of expensive optics to correct for atmospheric disturbance?
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.
Heh, my wife is Native American, and there's a nasty secret here that most will admit if you press them on it. In the various tribal mythologies, almost EVERY halfway interesting tall mountain, plateau, valley, canyon, rock, or steep hill has some kind of ancient legend associated with it and could be construed as "sacred". In fact, in my wifes tribal tradition ALL mountains are the homes of the gods, and building on ANY mountain is defilement (no, she doesn't actually believe that, but there ARE still a few nutballs that do).
Unless there's a burial ground at the top, the term "sacred mountain" doesn't mean much to me.
There is nothing so pathetic as seeing a beautiful young theory roughed up by a tough gang of facts.
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?