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Powerful Optical Telescope Captures First Binocular Images

Soulskill posted more than 6 years ago | from the i-can-see-clearly-now dept.

Space 83

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.'"

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And when they peered into the telescope (-1, Troll)

Anonymous Coward | more than 6 years ago | (#22683460)

Re:And when they peered into the telescope (-1, Troll)

Anonymous Coward | more than 6 years ago | (#22684270)

Excellent work, mods. Really now. Bravo. You really showed him! After all, it's much more humiliating for an anonymous link to goatse to be modded as "-1, Troll" rather than just plain "-1".

Cunts.

Been done (4, Funny)

akuykenda (994933) | more than 6 years ago | (#22683504)

It will provide unmatched ability to peer into history, seeing the birth of the universe.


Something like that already exists [wikipedia.org] .

Re:Been done (0)

Anonymous Coward | more than 6 years ago | (#22684950)

I was always partial to the tardist [nekochan.net] .

Re:Been done (3, Insightful)

hey! (33014) | more than 6 years ago | (#22686438)

You can't use a TARDIS to witness the birth of the universe any more than you can use an airplane to see what's north of the North Pole.

Re:Been done (1)

ClownSoup (1138593) | more than 6 years ago | (#22690446)

Sure you can. Once.

Season 19, Episode 1, Castrovalva

captcha: thighs. Like those on Teagan. mmm.

Just like the movies (3, Funny)

Fear the Clam (230933) | more than 6 years ago | (#22683558)

Everything will seen through an infinity-symbol-shaped viewing area.

Re:Just like the movies (1)

lazy genes (741633) | more than 6 years ago | (#22685642)

Untill the new three lens model appears.

ya .... so, where's the wallpaper? (1, Insightful)

Anonymous Coward | more than 6 years ago | (#22683568)

I can only hope the astronomy community will remember where its funding comes from and repay us with many more downloadable images in wallpaper resolutions.

Personally, I can't think of a better way to promote space, oh, wait, except maybe a real space station ,,,

The Birth of the Universe, Wow! (1)

rbrander (73222) | more than 6 years ago | (#22683616)

And, you know, It Must Have Been A Beautiful Baby, Cause Baby, Look At It Now...

life ain't fair (1, Funny)

budgenator (254554) | more than 6 years ago | (#22683658)

I'd be happy with a binocoular telescope that had pair of 15 cm objective mirrors and they get a pair of 840 cm mirrors.

Re:life ain't fair (3, Informative)

siddesu (698447) | more than 6 years ago | (#22684640)

make one yourself. some [foothill.net] people [stargazing.net] do [binoscope.co.nz] ;)

Re:life ain't fair (1)

budgenator (254554) | more than 6 years ago | (#22686102)

yeah those are real cool instruments. I'd lean toward using a Nasmyth [wikipedia.org] style design and have more separation between the objectives to make the observations more comfortable.

Not Quite Right.... (0)

Anonymous Coward | more than 6 years ago | (#22688212)

There is a difference between this type of telescope and the links people have beeen posting about "Binocular Telescopes". This scope uses 2 separated mirrors to do interferometry [wikipedia.org] , which essentially simulates the angular resolution (sharpness) that a telescope with a much bigger mirror (a mirror the size of the separation between the two mirrors) would get. The links posted about binocular telescopes are amateur scopes that just have two separate optics systems so the user can look with both eyes. NOT the same as what this scope does!

Peeping tom (2, Funny)

artichokesquid (1252062) | more than 6 years ago | (#22683680)

No hot chick changing clothes in her room will be safe now ...

This might be a stupid question... (4, Interesting)

TubeSteak (669689) | more than 6 years ago | (#22683682)

If two telescopes are good, wouldn't three be even better?
It's not like two is some arbitrary limit... right?

Re:This might be a stupid question... (2, Funny)

Deadstick (535032) | more than 6 years ago | (#22683696)

If two telescopes are good, wouldn't three be even better?

Certainly would, and your contribution will be deductible.

rj

Re:This might be a stupid question... (1)

lexarius (560925) | more than 6 years ago | (#22683720)

I don't recall much from Computer Vision, but multiple cameras are great, especially if you're missing information. But (I think) if you've got a well-calibrated stereo system, it's probably more useful just to get more pictures over time and/or from different angles.

Re:This might be a stupid question... (1)

Hynee (774168) | more than 6 years ago | (#22688014)

You don't get stereo vision of the skies using the LBT, but you can increase the resolution using interferometry.

Re:This might be a stupid question... (2, Informative)

the_other_chewey (1119125) | more than 6 years ago | (#22683832)

If two telescopes are good, wouldn't three be even better?
It's not like two is some arbitrary limit... right?

Right. VLT [wikipedia.org] has four.

Re:This might be a stupid question... (5, Informative)

Elrond, Duke of URL (2657) | more than 6 years ago | (#22683870)

No, there's no physical limit to how many you can have. But, of course, cost is a factor. The construction of the LBT was very expensive. Each of the 7.5m mirrors alone cost a fortune to construct.

On another mountain outside of Tucson (Mt. Hopkins) is the MMTO (Multiple Mirror Telescope Observatory). As the name suggests, this was a large telescope made from six smaller mirror segments. It has since been converted into a telescope with a single 6.5m mirror. There's a group at the University of Arizona which does adaptive optics experiments with it (MMTAO).

Re:This might be a stupid question... (0)

camperdave (969942) | more than 6 years ago | (#22683880)

Didn't some Earth microbe kill off all you three eyed Martians?

That's quite right - And the future of astronomy. (4, Informative)

Esteanil (710082) | more than 6 years ago | (#22684046)

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.

Re:That's quite right - And the future of astronom (1)

johannesg (664142) | more than 6 years ago | (#22685412)

Serious question: is the light that can be collected a few hundred meters away better or even different from the light that can be collected close to each other? In other words, is a group of small mirrors with the same surface area as a single large mirror inherently better? Or is this simply a matter of launcher-logistics (i.e. maximum launchable mirror size)?

BTW, I did a lot of work on the Herschel spacecraft ;-) But not on the optics, and I'm not an astronomer...

Re:That's quite right - And the future of astronom (2, Interesting)

a_claudiu (814111) | more than 6 years ago | (#22685516)

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.

Re:That's quite right - And the future of astronom (1)

Ihlosi (895663) | more than 6 years ago | (#22685870)

In other words, is a group of small mirrors with the same surface area as a single large mirror inherently better?

It's not "better", it's "just as good" while being vastly, vastly cheaper. Also, it's not the surface area itself that matters for resolution. So several small mirrors (with a smaller surface area), spaced apart, can deliver the same resolution as one huge mirror.

Re:That's quite right - And the future of astronom (1)

theguyfromsaturn (802938) | more than 6 years ago | (#22686492)

I am no expert, but as I understand it, the total amount of light collected is only a factor in increasing the power of the telescope. So, two telescopes of a certain size would collect the same amount of light however fare apart they were. However, when the light is combined they can use interferometry principles to obtain a higher resolution image than would be otherwise be possible from the same location (and no, the kind of distance apart that they are would not provide meaningful parallax info at stellar distances). So, having them further apart will increase the resolving power of the telescope. Basically, the distant stars and galaxies will look just as bright, but it's the difference between seeing a bright spec, blurred by maladjusted lenses, compared to a sharp image, with lots of detail given by well focused lenses. Total surface area provides brightness. Spacing provides detail and resolution. At least this is how I understand it. Those more knowledgeable will be able to answer better.

Re:That's quite right - And the future of astronom (1)

at_18 (224304) | more than 6 years ago | (#22694604)

Serious question: is the light that can be collected a few hundred meters away better or even different from the light that can be collected close to each other? In other words, is a group of small mirrors with the same surface area as a single large mirror inherently better?

There are two main factors determining the power of a telescope mirror.

1) Collecting area. A bigger mirror will collect more light and allow you to see fainter objects. A group of small mirrors will have a collecting area more or less equivalent to a single mirror with the same total area.
2) Resolving power, that is, the ability of detecting very small details. For diffractive optics reasons, this is proportional to the diameter of the mirror. If you have a group of telescopes, it is instead proportional to the distance between them, and if you can space them say 100 meters apart it's potentially *much* better. Such a system is called an interferometer [wikipedia.org]

Combining light in interferometric mode from two or more telescopes is difficult. For example, you have to know the exact distance between them within a small fraction of the wavelength you are observing. For optical or infrared observation, that means a small fraction of a micron. On the LBT, it is easier than usual because the two mirror are mounted on the same supporting structure. Radio interferometers are common because they work with millimeter and centimeter wavelengths, and beam combining is relatively easy.

Another problem is that an interferometer will "see" an image only along a single direction - it will detect changes in illumination (corresponding to the features in the image: borders, points, etc.) only if they are perpendicular to the line connecting the two mirrors. If you want a more or less complete image, you have to rotate the telescope with respect to the sky, or use many telescopes so that you have many different directions to play with.

Hope this helps.

Re:That's quite right - And the future of astronom (2, Informative)

Trapezium Artist (919330) | more than 6 years ago | (#22686146)

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.

Re:That's quite right - And the future of astronom (1)

gplus (985592) | more than 6 years ago | (#22686754)

I would have modded you up, but I also want to comment.

You're no doubt right that it's extremely difficult make a space telescope like Darwin a reality. But I still think that they should give it very high priority to make it happen. There's little you can do in science or space engineering that has more potential than this. Just imagine what an impact it would have, if we found a planet 15 or 20 light years away, that showed every sign of being teeming with abundant life. Just like Earth.

It would inspire school children, politicians, Hollywood and everybody else enormously, I think. People would demand an interstellar space probe sent out. Even knowing that it would take a century or more, before the probe could begin to send back pictures. NASA would have to develop some super ion engine or something, with interstellar capabilities. They would have something really inspiring to do again.

Re:This might be a stupid question... (0)

Anonymous Coward | more than 6 years ago | (#22684154)

plus, the astronomy nerds could say they had a three-way.

Re:This might be a stupid question... (2, Interesting)

hey! (33014) | more than 6 years ago | (#22686560)

IANAA, but I think the advantage of the binocular telesecope is resolving power, not light gathering power.

With conventional telescopes, a bigger telescope doesn't just "see" dim objects; it sees objects that are closer to each other (that is they have a small angular separation in the sky) than smaller telescope. So generally, bigger is better. The problem is that the difficulty of making precise optical components goes up very rapidly in size. The 200 inch Pyrex blank used to make the Hale telescope at Mt. Palomar weighed 40,000 pounds, and took a year to cool after it was cast. Naturally, it had to be figured to optical perfection, a process that took many years, and involved removing 10,000 lb of glass.

The idea here, I think, is to get the resolving power of a very large disk without the engineering complexities and cost. You do that but taking two largish but not heroically large mirrors, placing them 75' apart; then you carefully combine the light from each mirror to get the resolving power of a 75' mirror. This last process is tricky, but nothing compared to casting a 75' mirror, which would be over eight times the diameter and thus 64x the weight. It would take decades to create the blank, much less grid it.

I suppose you could add more mirrors than two, and there might be some advantages, but the chief advantage of the binocular arrangement is to get more resolving power for less (net) engineering cost. Since doing this kind of thing on this kind of scale is novel, and it's always a kind of bet when you do something new. Probably the best bet was to make two mirrors as large as you can afford then connect them in the simplest possible way that does the job, which rules out more mirrors.

For years, the U of Arizona had a telescope that combined the light from six 1.5m mirrors to make the equivalent of a single 4.5m telescope, so I suppose it's possible to use even more mirrors than two. The MMT arrangement was upgraded a few years ago to a single 6.5m primary mirror constructed from a hollow honeycomb matrix rather than a single massive Pyrex blank, and they recently added an adaptive optics secondary to improve the practical resolution of the telescope, so there's still some room to improve "conventional" ground based telescopes.

It's easy to imagine that in this century we'll see astronomical instruments an order of magnitude better than any currently in existence.

Re:This might be a stupid question... (0)

Anonymous Coward | more than 6 years ago | (#22711016)

The advantage is in both.

More light gathering leads to shorter exposures which leads to less image degradation.

Re:This might be a stupid question... (1)

Kingrames (858416) | more than 6 years ago | (#22690922)

NASA: "Fuck it, we're going to 4 telescopes!"

Re:This might be a stupid question... (1)

qinjuehang (1195139) | more than 6 years ago | (#22762672)

Actually, angular resolution is calculated using the distance between the furthest 2 telescopes, so it is not really that practical to have more telescopes. Of course, maybe less noise in the images and more light-gathering power, but would you do that if you are spending money on the magnitude of 7 and above?

Doesn't seem that large. (2, Interesting)

wozzinator (1079319) | more than 6 years ago | (#22683686)

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!

Re:Doesn't seem that large. (2, Informative)

megaditto (982598) | more than 6 years ago | (#22683780)

A single 840 cm mirror is like 9 yards across. Big, but not huge.

Re:Doesn't seem that large. (3, Informative)

Elrond, Duke of URL (2657) | more than 6 years ago | (#22683890)

The telescope is a ways outside of town on top of Mount Graham. I've not see it personally, but I've seen the building for the MMT (a much smaller telescope) on Mt. Hopkins and it is quite impressive.

The large building behind the football stadium on campus is the mirror lab where they cast and finish the individual mirrors. Even that building isn't so small.

Perhaps you are thinking of the small white domed building (Old Steward Observatory) that sits behind the current Steward Observatory? That's mostly graduate student offices now. There's a telescope in there, but it's very old and quite small.

Re:Doesn't seem that large. (1)

NixieBunny (859050) | more than 6 years ago | (#22683976)

I've been in the LBT a couple times. It's B-I-G! And it's on top of Mt. Graham, for which I have a red squirrel permit issued by USFS to visit the site for work purposes only. I don't know what telescope you're thinking of.

Re:Doesn't seem that large. (1)

wozzinator (1079319) | more than 6 years ago | (#22684186)

Ahh, I was thinking of the Mirror Lab next to the football stadium, I thought that is where they were housing the actual telescope. _lol_

Yeah, just 15 stories high... (1)

Physics Dude (549061) | more than 6 years ago | (#22685802)

I visited the LBT last fall and it seemed pretty large to me. The base of the building is about 5 stories high and the top part that houses the telescope and rotates is 10 stories high. It's a great tour.

If you missed Beowulf... (0)

hyades1 (1149581) | more than 6 years ago | (#22683690)

A high-quality binocular telescope starts work just when the next generation of 3D movie effects is rolled out. Am I the only one who's glad to live near a place that shows IMAX?

Re:If you missed Beowulf... (1)

hyades1 (1149581) | more than 6 years ago | (#22686872)

Oops. I seem to have run into a moderator with a very, very small soul.

BLT (5, Funny)

kck (16303) | more than 6 years ago | (#22683736)

I would have named it the Binocular Large Telescope.

Re:BLT (3, Funny)

NixieBunny (859050) | more than 6 years ago | (#22683990)

Yes, that would have been nicer. In a hallway in the Steward Observatory office building, there was once a poster illustrating the proposed Super Huge Interferometric Telescope I think the poster was done by bored grad students.

Re:BLT (1)

sarge apone (918461) | more than 6 years ago | (#22687194)

An afterschool program is being developed for urban high school students needing to recover credits for classes they failed so they can graduate on-time. One suggestion for the name was "Credit Recovery Instructional Program".

Re:BLT (2, Funny)

CraigParticle (523952) | more than 6 years ago | (#22689632)

Yes, that would have been nicer. In a hallway in the Steward Observatory office building, there was once a poster illustrating the proposed Super Huge Interferometric Telescope I think the poster was done by bored grad students.

We were NOT bored! Saved for posterity:
http://loke.as.arizona.edu/~ckulesa/superhuge/poster-halfsize.gif [arizona.edu]
and there was a BLT too:
http://daffy.as.arizona.edu/gradplays/play2k/blt.jpg [arizona.edu]

Hmmm. Actually... I guess we were bored...

Re:BLT (1)

astrobabe (533099) | more than 6 years ago | (#22705344)

Actually the SHIT poster was born out of the grad play. And BLT posters for the plat have been made for the grad play something like 5-ish years ago (god I'm dating myself).

Re:BLT (0)

Anonymous Coward | more than 6 years ago | (#22684890)

Why'd they drop the G anyway? (GLBT, nudge nudge wink wink)

Re:BLT (0)

Anonymous Coward | more than 6 years ago | (#22687328)

McDonald Douglas is already building one with that name. It keeps the hot side hot, the cold side ultraviolet.

First Binocular Images (0)

Anonymous Coward | more than 6 years ago | (#22683800)

And the first binocular images looked like this. [highlandgear.com]

Question (2, Funny)

PPH (736903) | more than 6 years ago | (#22683868)

If you look through the other end, do things look really, REALLY small?

Re:Question (2, Informative)

BigDaddyOttawa (948206) | more than 6 years ago | (#22683988)

No, they look really, REALLY far away.

So powerful that (-1, Troll)

antifoidulus (807088) | more than 6 years ago | (#22684008)

you can count the individual herpes sores on Britney Spears' genitals from across the globe.

Re:So powerful that (0)

Anonymous Coward | more than 6 years ago | (#22684158)

Meh... you can do that with the naked eye from the same distance.

Obviation of space borne telescopes? (1)

Ngarrang (1023425) | more than 6 years ago | (#22684146)

The ground-based telescopes are getting ever larger and more powerful. Atmospheric disturbance effects are nullified easily now. Are there any space telescope types that won't be obviated by these advancements?

weather (1)

nixeagle (1237044) | more than 6 years ago | (#22684262)

Earth based telescopes are still limited by clear nights without cloud cover. Space based telescopes don't have this restriction. Also earth based telescopes are limited to the times of the day the sun is not up. ;)

Re:Obviation of space borne telescopes? (5, Informative)

arse maker (1058608) | more than 6 years ago | (#22684264)

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 :)

Re:Obviation of space borne telescopes? (2, Insightful)

budgenator (254554) | more than 6 years ago | (#22686242)

Even when the skies are clear, it's getting pretty hard to find skies that are Dark [wikimedia.org] ; 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.

Holographic Telescope? (1)

Doc Ruby (173196) | more than 6 years ago | (#22684368)

Isn't there a way to make a "holographic sensor" into which light from a telescope could be directed, which would give the same increase in visual completeness that holograms give over stereographic imagery?

Re:Holographic Telescope? (1)

mazarin5 (309432) | more than 6 years ago | (#22684832)

Well, two of many reasons why this is better are:
1. Double the telescopes means double the light being captured; when you're trying to see objects that are very, very far away this is a good thing.
2. Slightly different positions means slightly different paths of light through the atmosphere. This helps reduce distortion through comparison.

Re:Holographic Telescope? (1)

a_claudiu (814111) | more than 6 years ago | (#22685998)

No. Not even stereographic imagery is not possible. The distance to stars is too big. To have the equivalent of distance between eyes you will need very very big distances between the 2 telescopes.

For having a holographic image you'll need a laser, split the light in 2 coherent rays pointed to the star, and record the resulting reflexions interferences. Not even Enterprise have the required technology.

Re:Holographic Telescope? (1)

budgenator (254554) | more than 6 years ago | (#22686256)

You can take pictures of objects 6 months apart so you can have your "eye distance" the diameter of the Earth's orbit which will mike near objects stereographic.

Re:Holographic Telescope? (2, Informative)

Doc Ruby (173196) | more than 6 years ago | (#22686352)

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.

Re:Holographic Telescope? (1)

ceoyoyo (59147) | more than 6 years ago | (#22687260)

Unless you make a negative refractive index material in the wavelengths you're interested in (and even those have limitations) your angular resolution is going to be limited by aperture. "Nanoscale optics" aren't going to help you out there. You can build interferometers, which DO help you out, but you're still limited by how far away from the planet you can get. We can do parallax measurements (much easier than actual stereo imaging) of objects that are near Earth, using the entire diameter of the planet's orbit, but for more distant targets we'd need to travel to other stars. Basic science maybe, but still a bit in the future.

Re:Holographic Telescope? (1)

Doc Ruby (173196) | more than 6 years ago | (#22688036)

Well, metamaterials are now available. And aperture is now greatly expanded in by "virtual" apertures, like scattered "subaperatures" sparsely filling a larger effective aperture area.

And as I said, orbital telescopes can get larger parallax, including solar orbits. Several different elliptical Solar orbits could give both large parallax and larger virtual apertures.

Re:Holographic Telescope? (1)

ceoyoyo (59147) | more than 6 years ago | (#22689508)

Metamaterials are not available outside microwave frequencies, and they don't blow away physical limitations, just let you circumvent them a little. Theoretically. Nobody's built a good microwave telescope out of metamaterials yet.

Yes, you can use interferometry and parallax measurements from different points in the planet's orbit. And we do. That gives you measurements of stars fairly close to us. Most astronomy these days is interested in looking at things a wee bit farther away than that.

Re:Holographic Telescope? (1)

Doc Ruby (173196) | more than 6 years ago | (#22689558)

That is all what science and engineering is for. I didn't ask whether there's a telescope available now. I started to explore ways to go further that don't require scientific breakthroughs, just some normal science and applying it in engineering.

It seems that what I want is possible, which satisfies me, for now.

Re:Holographic Telescope? (1)

a_claudiu (814111) | more than 6 years ago | (#22687402)

A few hundred thousand miles (opposite points on a geosynchronous orbit) is enough parallax
I don't agree that 2 photo taken at 2 different times makes a real stereographic imagery. Things are moving in 6 months. It will be as real as a computer generated image. Even then you'll be able to obtain only differences between positions of stars not differences between the image of the star itself. Maybe our definition of stereographic imagery differs.

Even a few centimeters would be enough
If you have a small distance between the the sensors you'll be able to see the difference in a photo only between the very close objects and the very distant one. The smaller the distance between sensors less spacial information you have.

I'm not sure you're ready to tackle holographic telescopics
You can not have a photo hologram without 2 coherent light sources one reflected from the object and one not. At least not what is called now hologram. This is done now via lasers. I assume that you don't know a laser powerful enough to go to Proxima Centauri and back, and you are not patient 8 years for the response in the correct place at the correct time.

Let's assume that you find a natural coherent light doing the job for you. You will still need to filter all the non coherent light coming from the sun itself and the reflected light (if it's reflected from the sun at all). I can not even think about holograms containing multiple stars.
If you really want you can "create" a hologram but not take one.

Maybe I'm not able to handle future "holographic telescopics" but I know what a hologram is.

Re:Holographic Telescope? (1)

Doc Ruby (173196) | more than 6 years ago | (#22688016)

The orbit can contain two different telescopes. And I was too constrained in saying "geosynchronous". In fact, there's no reason we can't launch two telescopes into a large orbit around the Sun, and take simultaneous images with larger parallax. But even a few hundred thousand miles around the Earth would be OK, with precision optics.

As for holographic telescopy (or whatever we call it), there are ways for non-coherent light to interfere with coherent light. The lasers don't need to reach the distant objects. It would take a lot of new engineering, but it could be worth it.

Re:Holographic Telescope? (1)

a_claudiu (814111) | more than 6 years ago | (#22688904)

1. Stereographic images. What is the scope of your images? For having a stereo image of an object as far as a star the Earth orbit parallax is much too small. For calculating the distances to the stars is almost useless (you can calculate easier) and making photos with a very close star in front of a very far away star it's cool but a kind of useless from scientific point of view.

2. Holograms.

there are ways for non-coherent light to interfere with coherent light
You are not making interferences for the sake of interferences, you want the result to give you data. In actual holograms all the image is composed of reflected light (coherent one) interacting with the original one for storing the difference. You will never see a fire in a hologram picture because is not reflecting light but produces it.

It would take a lot of new engineering
No. It will take a breakthrough and it will be called different, something like nanoholography (everything is nowadays nano).

Not the first stereo telescope (0)

Anonymous Coward | more than 6 years ago | (#22684948)

None of the source material for this article suggests that this is the first 'binocular' telescope, but the summary implies that this is the case. One example (among many) of previous telescopes to use this technique is the (now retired) Carnegie twin refractor at Lick Observatory.

All right! (1)

iminplaya (723125) | more than 6 years ago | (#22684996)

A giant View-Master

Is that a supernova? (2, Interesting)

dsvilko2 (1096853) | more than 6 years ago | (#22685550)

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.

Re:Is that a supernova? (1)

dsvilko2 (1096853) | more than 6 years ago | (#22685648)

Here is the link to the SDSS image: http://www.astro.washington.edu/west/rc3/NGC2770.jpeg [washington.edu]

What are the advantages of a binocular telescope? (2, Interesting)

TropicalCoder (898500) | more than 6 years ago | (#22686192)

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... [binoscope.co.nz]

"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."

Re:What are the advantages of a binocular telescop (3, Informative)

dsvilko2 (1096853) | more than 6 years ago | (#22686362)

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.

Re:What are the advantages of a binocular telescop (1)

TropicalCoder (898500) | more than 6 years ago | (#22686406)

The other is the resolution gain that is possible with the binocular setup through interferometry.

Could you please elaborate on that? I found one of the original research papers that led to this telescope, and it said something like "the advantages of a binocular telescope to interferometry are well known" - not very helpful to us non-astronomers.

Re:What are the advantages of a binocular telescop (1)

VENONA (902751) | more than 6 years ago | (#22690944)

Resolution increases linearly with aperture. The effective aperture for the LBT would then be the separation of the two telescopes plus twice the aperture (8.4 m) of either. You only get that increased resolution directly along only one axis--the one through both telescopes. So you take multiple images and do some math, and in many cases you should be able to arrive at the max resolution--which is equivalent to a single instrument of 22.8 m aperture.

See my post above, open the 'why build' link in another tab, and scroll down to the simulated infrared images of Io. Now see
http://www.keckobservatory.org/article.php?id=54 [keckobservatory.org]
which is another image of Io in infrared, from Keck, which is a very large, highly-capable system, at one of the best sites in the world. If the LBT reality is as good as the simulations--wow.

BTW, the light-gathering power varies as the square of aperture. So this pair of 8.4 m mirrors gives you the equivalent of a single 11.8 m instrument. So as a light-bucket, it's quite as much of a win as it is in resolution. But 11.8 m is still huge. The Keck telescopes are 10 m., for instance, and astronomers were stoked about them coming on line.

This stuff knocks me out. I remember seeing images of the Jovian moons in which you barely tell Io was a bit off-white.

Re:What are the advantages of a binocular telescop (1)

VENONA (902751) | more than 6 years ago | (#22690760)

I don't know why authors don't point to original sources instead of news sites.

http://medusa.as.arizona.edu/lbto [arizona.edu]
has links to the press release, but a lot of other stuff as well, including why it was built at:
http://medusa.as.arizona.edu/lbto/why.htm [arizona.edu]
and information about the telescope, including photos, at:
http://medusa.as.arizona.edu/lbto/telescope.htm [arizona.edu]

The 'why it was built' article could have answered the speculation in many of the above posts.

180 degree shift? (1)

rubydooby (1000318) | more than 6 years ago | (#22697534)

What kind of resolution would something like that have if it was in orbit... pointed at us?
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