ESO's Very Large Telescope Now Delivers Images Sharper Than Hubble (eso.org) 139
ffkom shares an excerpt from a press release via the European Southern Observatory: ESO's Very Large Telescope (VLT) has achieved first light with a new adaptive optics mode called laser tomography -- and has captured remarkably sharp test images of the planet Neptune, star clusters and other objects. The pioneering MUSE instrument in Narrow-Field Mode, working with the GALACSI adaptive optics module, can now use this new technique to correct for turbulence at different altitudes in the atmosphere. It is now possible to capture images from the ground at visible wavelengths that are sharper than those from the NASA/ESA Hubble Space Telescope. The combination of exquisite image sharpness and the spectroscopic capabilities of MUSE will enable astronomers to study the properties of astronomical objects in much greater detail than was possible before.
Slashdot, please help clean up Slashdot (Score:1, Insightful)
Please Slashdot, can you stop all these trolls from polluting the Slashdot space. In the past the comments by users were of an interesting nature related to the subject story, but now on 5% maybe is about the story as trolls post rubbish about Politics, Defamation, Racist and such other crap. I have emailed you before but as usual not one slashdot company person could be bothered to reply. Moderation is not really working, as there are only 5 points per moderator so it can take ages to clean up threads. Per
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says someone posting as AC.
And no. requiring membership or taking away anonymity has a chilling effect.
The only way to have truly free speech and expression is the right to anonymity.
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What's more chilling?
Not being able to post anonymously or having a moderation system that is an invitation to abuse?
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I can follow you, up until your last sentence.
Pseudo-anonymous accounts are perfectly viable, certainly on slashdot. Have been using them for years, and never got any spam or harrassement. I mean, not outside of the commentary/thread itself.
I've never quite understood the 'online harassment' claim, frankly. Certainly not when one is posting with nicknames that don't (cor)relate with your real person. You can always just decide to not read trollish posts or put spam in the bin or auto-filter it. Straightforw
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AC means no consequences for posting spam, stupid shit, attacks, etc.
Pseudo-anonymous at least have a mechanism to punish those behaviors, even rating comments at -1 initially, something that ACs avoid.
Of course using your real info is just insane for all the reasons you mention.
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The GP of course is a Troll seeking to make it look like there is a desire to close down free speech. Slashdot posting mechanisms and moderation seem to be working just fine. A concerted spam attack by a government agency could well be on its way if the GP is actually paving the way for it.
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Re:Slashdot, please help clean up Slashdot (Score:5, Insightful)
Re: Slashdot, please help clean up Slashdot (Score:1)
The AC you're replying to is a moron. The filters he's describing already exist, and trolls have become very good at evading them.
I do take issue with you saying that moderation is effective. Many obviously bad posts remain at 0 rather than being modded to -1. The volume of posts makes crapflooding somewhat effective against moderation. It also spends mod points on bad posts that would be better used to promote good posts. This was, indeed, less of an issue in the past. Editors have unlimited mod points and
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Funny how people reply to this obvious troll, like if it was a serious claim. Anyway we should keep AC posting as it is useful sometimes (and moderation does work).
Slashdot's moderation system does indeed work. And there is a level slider we can use to cut off anything below a certain level. Cut off anything below 1, and it cleans the neighborhood up right nicely.
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Hey! I remember watching that playlist! :)
Playlist details:
Video 1: Stan Lee coming to comic con
Video 2: Stan Lee not coming to comic con
Video 3: Stan Lee coming to comic con
Video 4: Stan Lee not coming to comic con
Video 5: Stan Lee coming to comic con
Video 6: Why I said Stan Lee was coming then, not coming to comic con
--
Balena!
Re: Slashdot, please help clean up Slashdot (Score:5, Insightful)
In the past the trolls were funny and interesting. Natalie Portman and hot grits, the saga of OpenSourceMan, The Turd Report, even OGG THE CAVEMEN until the cops lock filter silenced him. Now its just APK and the anti trump guy.
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Re:Slashdot, please help clean up Slashdot (Score:5, Informative)
Please Slashdot, can you stop all these trolls from polluting the Slashdot space. In the past the comments by users were of an interesting nature related to the subject story, but now on 5% maybe is about the story as trolls post rubbish about Politics, Defamation, Racist and such other crap....yada yada
You see that sliding bar thing at the top of the screen? Yeah, that one...
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You see that sliding bar thing at the top of the screen? Yeah, that one...
I agree with everyone who notes that Slashdot’s moderation system does work - but I can see the AC’s point.
When I first started reading Slashdot (back in the early 2000’s), I quickly noticed that a significant percentage of Anonymous Cowards would make interesting points. So I always read with my threshold set at 0, and mentally filtered the garbage posts out.
But over the past several years, the number of garbage posts has increased dramatically... and the tone of many of them is now just
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That anti Trump guy must still live at home. Who has enough time to be the first to reply to every single story? I do give him credit for being able to keep that mighty Fedora upright on his head.
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Agreed, Slashdot's hands-off approach to trolls has driven away the knowledgeable members, academics, and experts that used to make Slashdot great. It is a shame. HOWEVER, moving that discussion slider bar to browse at 0 or 1 does do wonders. It's not enough to bring back Slashdot back to it's glory days of contributors, but it makes it passable now.
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I don't want to cast unfair aspersions on the pointiness of this new telescope, but, IIRC, the Hubble Space Telescope was fairly blunt, and is not a high benchmark for judging the acuteness of new observatories.
Fair enough but, unless you actually want to cast aspersion, could you please get your facts straight Mr. AC? Although new instruments become operational on a regular basis, this "new" telescope has been operating since 1997.
RT.
Don't over generalize (Score:1, Redundant)
The achievement is that due to adaptive optics, an earth based telescope can deliver pictures as sharp or sharper than a space based telescope.
Close. What it proves is that we have advanced technology enough that an Earth based telescope can deliver pictures sharper than the Hubble. One cannot generalize this to all space based telescopes since we are now capable of creating space telescopes that exceed the capabilities of Hubble. Remember Hubble was launched in 1990 so it's basically 1980s technology and things have progressed since then.
Don't over minimize (Score:5, Interesting)
Only partially true. Space-telescopes still have an advantage in some area's, especially for the deep and near-infrared wavelengths, and ultraviolet wavelengths, but the other advantages are becoming less and less obvious, especially if you consider the cost of both space-based as Earth-based telescopes.
The disturbances of the atmosphere - the major drawback (diffraction limit) up until the last decade of the 20th century - have become largely reduced thanks to adaptive optics and other technological advances.
The argument that we are now capable of constructing space-telescopes that are better than Hubble has no bearings on the comparative advances, since we can also create better earth-based telescopes than VLT, these days. As the Extremely Large Telescope will show, no doubt. There is little doubt this latter one will exceed the JWST, just as the VLT did with Hubble - IF the JWST was going for the visible light waves, which it isn't. In fact, it's the main reason Beryllium mirrors were used that excel in infra-red wavelengths, about the last advantage space-telescopes still have that warrant the vastly more expensive cost (now at more than 10 *billion* for the JWST, if I remember correctly).
Note that for that price, you could have made 10 Overwhelmingly Large Telescopes (OWL) which would completely DWARF the JWST on almost all other fronts, certainly when using interferometry.
Excessive extrapolation (Score:2)
The argument that we are now capable of constructing space-telescopes that are better than Hubble has no bearings on the comparative advances, since we can also create better earth-based telescopes than VLT, these days.
True in both cases but irrelevant to my point. The point is that one should not extrapolate this result too far. We have ground based telescopes now that under some conditions can exceed the results from Hubble. That is ALL you can say. It doesn't say anything about the relative capabilities of current leading edge ground or space based telescopes in general.
All other things being equal a space based telescope should get better results than a ground based one no matter how good the optical correction is
Re: Excessive extrapolation (Score:2)
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There is no such thing as an uninterrupted view in all angles and directions, if one stays in Earth's orbit - and certainly not a low Earth orbit, as the HST does.
0ne can get longer uninterrupted exposures in some directions, especially if you move out of Earth's low orbit, but the question is, if that's relevant. Deep field imagery is depended on the lightgathering, which, indeed, is dependent on exposure-time BUT even far more so on aperture size. Meaning, you can see far more with a bigger aperture in l
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"True in both cases but irrelevant to my point."
Granted, but then you shouldn't have used it in substantiation of the point.
The original point being: "The achievement is that due to adaptive optics, an earth based telescope can deliver pictures as sharp or sharper than a space based telescope."
Which, basically, is true. As we seem both to agree, the fact that one can built better space-telescopes does not change or counter anything to the above claim, since better Earth-based telescopes can be built as well
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Perhaps in 50 years we have space telescopes orbiting behind the Pluto orbit, using the sun as gravity lens. Imagine what you could see with them ...
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Re:Don't over minimize (Score:5, Informative)
The diffraction limit is not due to atmospheric effects. It is a fundamental limit imposed by the aperture of your telescope, which is more or less the size of the primary mirror.
It's currently easier to make a large aperture telescope on the ground, but with the bigger ones it's hard to achieve the diffraction limit because of atmospheric effects. The very best adaptive optics only get you to Hubble territory. JWST is bigger than Hubble.
Interferometry, particularly image-forming interferometry, is probably easier in space. You've got all the space you could possibly want, you can use free space lasers instead of fibre optics, and you can arrange for your telescopes to move easily to produce the image; on the surface you need to put them on train tracks.
Technically, big mirrors are easier in space too, since they don't have to support themselves against gravity. The current problem is you have to get them up there.
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"The diffraction limit is not due to atmospheric effects. It is a fundamental limit imposed by the aperture of your telescope, which is more or less the size of the primary mirror. + /but with the bigger ones it's hard to achieve the diffraction limit because of atmospheric effects"
Indeed. The larger the aperture, the more the disturbances are visible and noticeable as well. At a certain point, you gain nothing in resolution (though you still gather more light), even with bigger mirrors.
"The very best adapt
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The original estimate was officially 1 to 1,2 billion euro's (in 2006 currency). The *original* estimate that is. But we all know how that goes, with large projects. ;-)
That said, let's say it would have been double that amount in reality. It still would mean 4-5 OWL's. Even one OWL would produce better pictures than JWST would ever be able to, let alone 5 with interferometry...
It would have outclassed JWST without any doubt.
(If, I repeat, JWST would have been in the visible wavelength as well, which it isn
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Only partially true. Space-telescopes still have an advantage in some area's, especially for the deep and near-infrared wavelengths, and ultraviolet wavelengths, but the other advantages are becoming less and less obvious, especially if you consider the cost of both space-based as Earth-based telescopes.
Space telescopes not only have advantage in some wavelengths, but they are critical, since parts of the spectrum are blocked by the atmosphere. Additionally they have practically round the clock observing time.
The images are very impressive though. There is place for ground based telescopes, airborne (SOFIA) and space telescopes - they are complementary.
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"Space telescopes not only have advantage in some wavelengths, but they are critical, since parts of the spectrum are blocked by the atmosphere."
Which was why I said they still had advantages in those area's. ;-)
There needs to be a compelling reason to send a telescope in space that costs 10 times more for 10 times less aperture. Difficulties to get close to the diffraction limit used to be one of those, up until the late 20th century, but this reason has been starkly reduced with the advent of adaptive opt
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I agree with you, advances in adaptive optics are amazing and ground based telescopes are much less expensive, that is why we have so much more of them comparing to the space telescopes.
However both are critical for scientific progress, there are things, which can only be done from space due to absorption by the atmosphere (it is not like space is better, simply the science cannot be done from the Earth surface), additionally there was no such technology when Hubble was launched. Just because in e.g. 20 ye
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Well... let's not just brush it off as one single management failure with no precedence.
Note that even the HST was hugely over budget, over time, and was mismanaged as well... so it's not like it's a one-time thing. Instead, it's more common than not.
From its original total cost estimate of about US$400 million, the hubble space telescope cost about US$4.7 billion by the time of its launch. Hubble's cumulative costs were estimated to be about US$10 billion in 2010. It was launched years behind shedule. It h
Aim it at the moon... (Score:3)
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...and take pictures of the Apollo landing sites. That should shut a few mouths.
No, it won't. When someone "wants to believes", facts won't change their opinion. They will see VLT as part of the conspiracy.
Re:Aim it at the moon... (Score:5, Informative)
[1] MUSE and GALACSI in Wide-Field Mode already provides a correction over a 1.0-arcminute-wide field of view, with pixels 0.2 by 0.2 arcseconds in size. This new Narrow-Field Mode from GALACSI covers a much smaller 7.5-arcsecond field of view, but with much smaller pixels just 0.025 by 0.025 arcseconds to fully exploit the exquisite resolution.
tan( 0.025 arcseconds ) = 1.2120342e-7
distance to the moon is 384.4 million meters
1.2120342e-7 * 384.4e6 = 46.59 meters
tl;dr: Still about 2 orders of magnitude away from being able to take a blurry ass 15x20 pixel image of the lander. Try again in a few decades.
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a blurry ass 15x20 pixel image of the lander
Blurry ass? Are you saying the lander is mooning us?
Re:Aim it at the moon... (Score:5, Informative)
The Rayleigh criterion [wikipedia.org] then tells us that to resolve something that small using blue light (shortest wavelength) would require telescope optics that are:
You might be able to do it with an interferometer [wikipedia.org]. This is done all the time with radio telescopes [wikipedia.org] - each dish acts as a single point on a very large mirror aimed at the same spot in the sky. But an interferometer needs to be aligned within a quarter wavelength of the light you're using. Relatively easy with radio waves, not so much with visible light.
Anyhow, this is all a moot point. The Apollo missions left retroreflectors [wikipedia.org] on the landing sites. These are mirror arrays which will reflect light back exactly 180 degrees. Scientists use them all the time to precisely measure the distance to the moon [wikipedia.org], thus proving that we've actually been there.
Re:Aim it at the moon... (Score:5, Insightful)
Besides, which fake moon landings derp is going to accept the picture as genuine when they already discount the evidence provided by the laser reflectors left on the moon [wikipedia.org] by three of the Apollo missions and two of the Soviet Lunakhod missions? The reflectors are still in use, so there's no reason why they couldn't acquire a suitable laser and bounce their own signal off them if they really wanted to, but then they'd need to discount their own evidence and it might detract from what this really is - a pathetically lame attempt to get some attention like those who claim the Earth is flat, so that's never going to happen.
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Disclaimer: I have never worked with the VLT.
And possibly damage the telescope too. The moon is vastly brighter than the kinds of things the VLT is meant to image, so if its optics and filters can't deal with that it would be bad.
Usually before doing observations, a dark frame [wikipedia.org] picture is taken without any light falling in (just keep the lid on) and a flat field [wikipedia.org] picture of the horizon is taken when the telescope is flooded with light. This is done to have reference pictures, those are used (among others) to get rid of false negatives (dead pixels) and false positives from the CCD/DSLR camera and to eliminate the effects of dust particles on the lens.
There exist dedicated moon filters [lovethenightsky.com] for t
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The laser reflectors could have been shot there by an unmanned mission ... just saying.
No it cannot image the Apollo landing sites (Score:2)
...and take pictures of the Apollo landing sites. That should shut a few mouths.
Even if that were possible, no it would not. People who believe in conspiracy theories have no interest in actual evidence.
In any case it's a moot discussion because it isn't possible. The moon is too far away for any technology we currently possess to take images of the Apollo landing sites from the surface of the Earth or low Earth orbit. The smallest resolvable object is still many tens of meters across - far too large to see something as small as the Apollo lander. The entire landing sites would fi
Re: Aim it at the moon... (Score:2)
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As if they would believe a picture that so many people with Photoshop could easily create today as oppose to something that was much, much harder to "fake" in the 1970's. If they don't believe the video that came back and the reflectors that were left behind then they aren't going to believe a picture from a telescope.
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We already have pictures of the Apollo landing sites that are far better than what this telescope can make. The Lunar Reconnaissance Orbiter [nasa.gov] has imaged all of the Apollo sites.
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Wasn't Hubble broken anyway? (Score:3)
IIRC they had to fly up and correct the lens with some contraption because someone/someteam had screwed up the numbers when building it.
Isn't that so?
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IIRC they had to fly up and correct the lens with some contraption because someone/someteam had screwed up the numbers when building it. Isn't that so?
IIRC the mirror was ground with gravity present. Then under zero G conditions it sprung back to an unanticipated shape.
Hubble optical flaw origin (Score:5, Informative)
IIRC the mirror was ground with gravity present. Then under zero G conditions it sprung back to an unanticipated shape.
Your recollection is incorrect. [wikipedia.org] It was ground very precisely to the wrong shape due to some incorrectly assembled testing equipment. The problem was actually noted prior to launch but the test results were ignored. Gravity or the lack thereof had no relationship to the problem with the shape of the mirror. It was simply made to the wrong specifications and then final testing failed to catch the problem.
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Also, you could test for the effects of gravity by turning it upside-down. If the mirror was still the right shape, then gravity is not an issue.
Re:Hubble optical flaw origin (Score:5, Informative)
Also, you could test for the effects of gravity by turning it upside-down. If the mirror was still the right shape, then gravity is not an issue.
Ah, grasshopper. You fall for the very reasonable assumption that the Hubble was flown with an incorrectly figured mirror because no one on the ground could test it properly and find out that this was the case.
That isn't what happened.
When the mis-figuring was discovered by NASA, in orbit, I too was stunned. How could the engineers have relied on just one test to verify it?
They didn't.
The mirror was over-budget, and behind schedule, and management at Perkin-Elmer wanted to ship it. The mis-assembled instrument was the contractually agreed method of mirror acceptance, and the one used in the figuring process. When engineers found after the figuring that simple tests showed that it was incorrect, P-E management didn't care, and didn't tell NASA.
There were people at P-E who knew perfectly well that the mirror would not work. But hey, the managers probably got bonuses when the mirror left the facility.
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My comment was already downthread of that info - in fact, a reply to it - no need to repeat it even more verbosely. The point was that if it was gravity related, there would have been an easy test for that.
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As my post above (written simultaneously with yours) indicates, they did know.
Spy Sky Fry [Re:Hubble optical flaw origin] (Score:1)
Some of the technology was related to military spy scopes, so there may have been some "military concerns" that mucked up inspections or followup. Being espionage-related, we outsiders don't get the full story.
Re:Wasn't Hubble broken anyway? (Score:5, Interesting)
IIRC the mirror was ground with gravity present. Then under zero G conditions it sprung back to an unanticipated shape.
No, Perkin-Elmer simply screwed up. And amazingly after finishing a 72-inch mirror and sending it into high orbit, they didn’t think of running the Foucault figure test that every amateur astronomer who has ever ground a mirror knows To do.
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This could get you started [wikipedia.org], anyway.
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I had the pleasure of attending a lecture several years back by the then project manager for the Hubble. His explanation was that the issue was a managerial one. The instructions for one of the test devices were (summarized) drill a hole, then paint the device black. But what was actually done was it was painted black, then the hole was drilled. This issue was discovered early enough to fix. Apparently the standard process at the time was to have the project heads rotated ever so often so that they wo
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One quibble (Score:4, Interesting)
But seriously - if you are going to claim that your earth based adaptive optics system will deliver sharper images than Hubble - show us a comparison.
Its worth noting that Hubble is a flawed instrument in a good location, but the claim has been made, so stand and deliver, ESO!
Re:One quibble (Score:5, Informative)
But seriously - if you are going to claim that your earth based adaptive optics system will deliver sharper images than Hubble - show us a comparison.
Try reading the article:
https://www.eso.org/public/uni... [eso.org]
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But seriously - if you are going to claim that your earth based adaptive optics system will deliver sharper images than Hubble - show us a comparison.
Try reading the article:
https://www.eso.org/public/uni... [eso.org]
Thanks for the link - but why the snark?
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why the snark?
"But seriously - if you are going to claim that your earth based adaptive optics system will deliver sharper images than Hubble - show us a comparison."
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why the snark?
"But seriously - if you are going to claim that your earth based adaptive optics system will deliver sharper images than Hubble - show us a comparison."
So , Was that the link in the article? I went again, concerned at my stupidity because I didn't see the very obvious comparison - no, it was not the link. Perhaps I'm supposed to have ESP or something - but the link you gavee me pointing out my stupidity was not in the summary at all.
tl;dr version. You could choose to be anything, but for some reason you chose to be a condescending asshole - twice. At least now I am quite clear on why you chose to be snarky. It's how you are. Good day, sir.
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So , Was that the link in the article?
Yes, it's in the right-hand margin, with the caption:
"PR Image eso1824c [eso.org]
Neptune from the VLT and Hubble "
You could choose to be anything, but for some reason you chose to be a condescending asshole - twice.
Maybe you should look in the mirror. My replies were rather tame and to the point. If you don't like being treated this way, don't cast aspersions on others when the failing is yours.
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Not to take sides, but it was pretty clearly shown at the right of the summary, which is still 'the article', and it even says "Neptune from the VLT and Hubble". A cursory look would have been enough to find it. As I did.
While true it could have been put nicer, you're exaggerating with 'ESP' as well. And in your rebuttal you weren't very nice neither. In the end, he did give you the link for your request, so maybe you should have stayed a bit more polite as well, if you're going to complain about it in the
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Not to take sides, but it was pretty clearly shown at the right of the summary, which is still 'the article', and it even says "Neptune from the VLT and Hubble". A cursory look would have been enough to find it. As I did.
While true it could have been put nicer, you're exaggerating with 'ESP' as well. And in your rebuttal you weren't very nice neither. In the end, he did give you the link for your request, so maybe you should have stayed a bit more polite as well, if you're going to complain about it in the first place.
Dude - I do admit I'm a major asshole. And I also explained that my script blockers kept the image from ever showing up on my screen. Shields down, and I could see the comparison photos. Shields up, and I saw only one image, nothing else.
So yes - the problem was on my end, and major mea culpas all around. Anyhow, I'm suitably chastised, so I'll probably just let it go.
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Fair enough. :-)
Are you using ublock? Otherwise I recommend that. It's pretty good, and I have had very few problems with it (false positives included) on any site, thusfar.
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The article has a slideshow at the top that is a comparison of hubble images vs this new ground-based telescope.
Ah - that would answer it. I have so many script and ad blockers that the slideshow never presented itself.
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If you had read the article link provided in the summary you would have seen the image to the right of the text with the link that Raenex provided (Hint: on the right find "Images" third image down with caption "PR Image eso1824c/Neptune from the VLT and Hubble." Why are you being so snarky when you obviously only read the summary?
I've got a lot of stuff on my browser to keep the bad guys out, so that didn't show up.
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It is incorrect to say that the Hubble is currently flawed in any optically significant way. The Hubble main mirror was shaped incorrectly, but the error was a very precisely determined error in the large scale shape. Thus corrective optics could be designed and installed, providing the full capability of the instrument. This is not much different from almost any other astronomical telescope -- a single lens or mirror is not capable of the best possible optical performance, so telescopes have more than o
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It is incorrect to say that the Hubble is currently flawed in any optically significant way.
I suppose that you might say that depending on how you define flawed. I need corrective optics to allow me to see with proper vision. In my estimation, my eyes are flawed, and the lenses I use - no line bifocals and computer glasses make a big difference. Note to Slashdotters - Computer glasses are wonderful. Corrected for the distance from eyes to screen, they are a big help, and surprisingly inexpensive. They aren't reading glasses. Mine focus at ~ 30 inches and are sharp as a tack
http://hubblesite.o [hubblesite.org]
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Err the comparison is in the article.
Also the Hubble isn't a flawed instrument. It was a flawed instrument but after the optics were corrected it is very much an instrument that matches the spec that was originally supposed to be built to, and more given how the process of trying to correct the images while waiting for optics produced new breakthroughs in image processing.
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Err the comparison is in the article.
Also the Hubble isn't a flawed instrument. It was a flawed instrument but after the optics were corrected it is very much an instrument that matches the spec that was originally supposed to be built to, and more given how the process of trying to correct the images while waiting for optics produced new breakthroughs in image processing.
I guess you would say that my eyes are as close to perfect as possible because my glasses give me 20/20 plus vision?
It's usless pedantry to say the Hubble isn't a flawed device. It was polished incorrectly, and sadly, I could have determined that fact with a Foucault tester I could make in my garage in 20 minutes. There is another mirror sitting in a warehouse in Rochester, IIRC, that is ground and polished to as close to perfection as could be done.
If that back up mirror had been the one sent to spac
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Also, they had to remove a scientific instrument to make room for the corrective optics.
There is no doubt it was a kludge, and an expensive one at that. And a completely avoidable one. For the PRIMARY mirror - the main piece of the space-telescope - to be flawed in such an endeavor... you'd either need to be willfully turn a blind eye or be incompetent beyond belief.
Even NASA doesn't go without blame, here. They should have checked it independently, before shipping.
If one doesn't want to fall in the trap o
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I guess you would say that my eyes are as close to perfect as possible because my glasses give me 20/20 plus vision?
No I would not. Your eyes are a function of biology and the glasses are a function of a man made optical correction. I would say that the entire system which is your eyesight is close to perfect, but not your eyes.
The Hubble on the other hand was a human made optical system before and with the adjustment lens is a human made optical system afterwards. On top of that Hubble doesn't have glasses. The corrective lenses aren't even in front of the optical train so they have very little in common with your glass
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https://www.nasa.gov/content/h... [nasa.gov]
yes but (Score:2)
That said, they had to remove a scientific instrument to make room for the corrective optics.
Cool ESO video (Score:3)
Long ago, about early 1980s, in a galaxy... (Score:2)
Shine lasers to create fake twinkling stars, watch the fake stars twinkle, use motors to distort your telescope mirror 1000x a second to un-twinkle the stars, and thus also the image of what you're looking at.
"Star Wars" SDI tech IIRC. Anyway very cool.
Science-hating liberals strike again (Score:2)
That VLT was intended to have a Northern Hemisphere companion, the Thirty Meter Telescope, to be located in Hawaii. The two similar instruments could have cooperated to cover the whole sky and to perform long-baseline observations in the band where they overlap. But the anti-science community now classifies large research telescopes as evil infrastructure, like nuclear plants. Back in the Nineties they tried to kill off the newest large scopes here in Arizona, but we ran them off before they could do any d
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The TMT was a multinational effort with no US taxpayer input, and has been fully funded. I'm still hoping that because China is one of the partners, that it will eventually be built in the Tibetan plateau, where there are already qualified sites for large telescopes in the future.
Spain has offered to host the TMT, but they don't have the high-altitude sites that would be appropriate for anything this size.
Optical Space Telescopes are Now Obsolete (Score:2)
This is why we'll never launch another successor to Hubble: you can do better from the ground for a fraction of the cost -- hundreds of millions instead of tens of billions.
The James Webb Space Telescope (which at this point may very well never fly) views in the infrared, which you can't do from the ground. $8 billion and counting.
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The JWST will be launched eventually, when we stop scewing around and give it to Elon Musk.
This could be a big victory for tax payers in US (Score:1)
Americans should be able to keep a greater portion of their US tax revenues that they earned.
The Europeans can keep the credit for all the stars they discover.
Everybody wins !
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