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ESO's Very Large Telescope Now Delivers Images Sharper Than Hubble (eso.org)
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.
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. Perhaps you could keep track of users (even if they post AC) and if they collect enough moderations points they can be banned to help clean up this space, unless of course Slashdot like to have a polluted comments space that turns most users away from reading or participating.
If you must know: The whole VLT project has cost about EUR 500 millions within the 15 years of construction. Source: the german entry for the whole Paranal Observatory, of which VLT is a part of.
...and take pictures of the Apollo landing sites. That should shut a few mouths.
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.
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?
We suffer more in our imagination than in reality. - Seneca
IIRC the mirror was ground with gravity present. Then under zero G conditions it sprung back to an unanticipated shape.
Your recollection is incorrect. 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.
...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 fit basically inside of a single pixel or close to it.
so comparable to a half day of DOD budget ?
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.
--- "To pee or not to pee, that is the question." ---
Do I have to use it in sneak mode?
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 just because there is less stuff in the way. However things are obviously not equal so the comparison becomes more complicated.
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!
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
ESO Chill 1 https://www.youtube.com/watch?... imo, worth watching.
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.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
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.
Table-ized A.I.
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 damage. Unfortunately they found an undefended blue state to nest in.
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.
Actually, 500M are about 3.5 days of Germany's defense budget, and about 0.64 days of the defense budget of the European NATO member states.
That said, they had to remove a scientific instrument to make room for the corrective optics.
--- "To pee or not to pee, that is the question." ---
Let's get the Europeans to shoulder the cost of space exploration.
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 !