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Powerful Optical Telescope Captures First Binocular Images
The Large Binocular Telescope consists of two 8.4-meter mirrors which function in tandem to provide resolution greater than that of the Hubble Telescope. The LBT's first "binocular" images were captured recently, marking the end to a long and laborious construction process. We previously discussed the LBT when images were captured from the first mirror to be installed. Quoting:
"The LBT ... will combine light to produce the image sharpness equivalent to a single 22.8-meter (75-foot) telescope. 'To have a fully functioning binocular telescope is not only a time for celebration here at LBT, but also for the entire astronomy community,' UA Steward Observatory Director, Regents' Professor and LBT Corp. President Peter A. Strittmatter said. 'The images that this telescope will produce will be like none seen before. The power and clarity of this machine is in a class of its own. It will provide unmatched ability to peer into history, seeing the birth of the universe.'"
Something like that already exists.
Everything will seen through an infinity-symbol-shaped viewing area.
If two telescopes are good, wouldn't three be even better?
It's not like two is some arbitrary limit... right?
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I go to school there and surprisingly enough the building that holds it is relatively small in comparison to other telescopes. I dono how they do it!
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I would have named it the Binocular Large Telescope.
If you look through the other end, do things look really, REALLY small?
Have gnu, will travel.
In 2015 the European Space Agency is planning to launch Darwin. 4 spacecraft. 3 light collectors (based on the Herschel design) and one hub where the light is collected. If it works out (the telescopes and the hub must stay in formation with millimetre precision), we'll have a space telescope with an effective mirror size of several hundred meters.
The objective is the study of extrasolar planets, and the telescope will record in IR for purposes of recording signs of life.
Multiple mirror telescopes in space are probably the only way we will get to the point where we'll have close up pictures of extrasolar planets the size of earth.
And we're getting there.
I'm a dreamer, the world is my playpen. But hey, I'm a serious person, I can't dream all the time.
Huge portions of the electromagnetic spectrum are absorbed by our atmosphere, for instance infra-red. These spectra are totally unobservable from earth and space based telescopes will always be needed. Other technical issues include how long you can sit observing a target, the earth is constantly rotating and while earth based telescopes can track an object it can only do it for a small portion of the day. A space based telescope can (depending on its location) observe a target uninterrupted for days, weeks, months or as long as needed. Now binocular telescopes with a few huge telescopes on earth and a few huge ones on the moon... or even Mars. Now that id like to see... but not so much fund :)
make one yourself. some people do ;)
It's almost the same with microprocessors. Are the multi core better than a very quick single core (e.g. 2x2Ghz vs 4 Ghz)?
In the case of telescopes how big can you make a mirror without imperfections and tolerant to temperature changes? And then are coming the logistic problems.
For multiple telescopes you can enhance the image, compensate for defects in individual mirrors or atmospheric distortions but in absolute terms you'll obtain a better image from a single telescope with the equivalent mirror surface. There are other problems as well but these are the first coming in mind.
If you compare this NGC2770 image with the one taken by SDSS (Google Earth), one star is clearly missing on the SDSS image (the brightest one). That would certainly explain the choice of the target but there is no mention on the linked article. Anyway, I expected a larger difference in resolution between the image taken by a 2.5m wide-angle telescope (SDSS) and a 2x8.4m binocular telescope.
Not true, I'm afraid: Darwin was not picked by ESA as one of the missions to be studied for the so-called L (large) slot for launch in 2017-2018 during the recent Cosmic Vision selection exercise. Large missions in the running for that slot are XEUS (large X-ray telescope), LISA (gravitational wave observatory), and TANDEM/LAPLACE (missions to the outer planets, Titan and Jupiter, respectively, only one of which would happen). All of these would be collaborations with other space agencies.
It was felt that the precision formation-flying and interferometric beam combination techniques needed to make Darwin work were not mature enough for implementation yet. The science it's aiming at is of very great importance and such a project will undoubtedly return for consideration in future rounds of Cosmic Vision, but I'd say there's little chance of something like Darwin flying prior to 2022-2025.
In passing, you're right that Darwin would have the angular resolution of telescope several hundred metres in diameter, but it wouldn't have the collecting area of such a telescope. For direct detection of terrestrial-mass exoplanets close to their bright parent stars, that's fine; for other science such as studying galaxies forming just after the Big Bang, a larger collecting area would also be required. Comparison of the parts of parameter space covered by projects as disparate as Darwin, LBT, JWST, and future ELTs (ground-based extremely large telescopes, diameters and collecting areas of 30-40m diameter, under development for 2015-2020) is non-trivial.
This was my question when I read the FA. Like another respondent, I thought that with the stars so far away there wouldn't even be any parallax. I decided to ask my friend Google what are the advantages of a binocular telescope and found this...
"So what does it feel like to actually use a large aperture binocular telescope? David gives us his account; Mind blowing is probably the phrase that springs to mind..."
"The incredible sense of total immersion in the reality of the experience is what binoculars are all about. It's astronomy at another level. Seeing the large globular cluster Omega Centauri for the first time almost made me fall backwards off the step. The depth and resolving power on this object is spellbinding. Moving just outside the field of view of this object and panning slowly towards it, you're firstly presented with a pitch black sky with a scattering of random stars. As you move onto the object your eyes and senses are completely overwhelmed. You can look deeper and deeper inside this cluster and there is always more to see. It feels as though I've arrived on the doorstep to this cluster in my spaceship."
"A definite three-dimensional feeling is present, the objects appear to float almost in front of you, even though this is obviously not possible due to the enormous distance of these objects. One explanation is an effect called chromatic stereopsis, which due to chromatic aberrations in your eyes makes the red and blue stars focus at slightly different distances. Simple things, like double stars that have never captured my imagination are suddenly transformed into objects worth gazing at. Smaller and much fainter globular clusters all benefited from the relaxing view using two eyes. The fainter globular clusters if viewed with only one eye, needed averted version to make them visible, however with both eyes open, they were blatantly obvious."
This amateur astronomer with a binocular 16" telescope concludes after 6 months of constant use: "So far I have not found any category of object to observe that does not benefit greatly from the advantages of a true binocular telescope."
Even when the skies are clear, it's getting pretty hard to find skies that are Dark; it doesn't take much light pollution to wipe out a 3 day exposure to see some really faint object. You have to find a location that typically has clear skies, is high enough to get you above most of the atmospheric turbulence, has dark skies and isn't likely to have a housing subdivision built next door two years after you put a multi-billion dollars instrument into service.
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Stereographic imagery is certainly possible. A few hundred thousand miles (opposite points on a geosynchronous orbit) is enough parallax. Even a few centimeters would be enough parallax if the optics were good enough, which nanoscale optics will evenually offer. Our radio (high frequency light) instruments already capture fairly precise and accurate light from 13.72B light years away (and years ago). That is just a matter of technology, not basic science. It can be done.
Since you can't figure out stereoscopic telescopics I'm not sure you're ready to tackle holographic telescopics.
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As an amateur astronomer I can say that what you wrote is absolutely true. It's something very different and wonderful to be able to observe with both your eyes even if the image they are getting is completely the same. Still, it has nothing to do with why people build large binocular observatories such as this. One reason is that it is probably cheaper to build two 8.4m mirrors that won't distort under their weight then one large mirror of the same surface area. The other is the resolution gain that is possible with the binocular setup through interferometry.