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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.
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.
If an IP or subnet accumulates enough negative moderation in a period of time, anonymous posting is temporarily disabled. There already are temporary bans, just like what you're asking for. The bans don't work because of trolls getting new IPs on different subnets and continuing to post. That's how they evade limits on the frequency of anonymous posts, as well. Are you going to track how much negative moderation each IP or subnet has ever received and ban based on that? That's ridiculous because they can affect multiple users, many of whom may have no connection to the trolling.
Slashdot has always had lots of trolls and crapflooders. There were probably more crapflooders in the past, many of whom had multiple accounts. Some of the accounts were for crapflooding while others were used for making productive comments. Many of the articles had tens of comments at -1, which is quite a bit more crapflooding than is actually going on now. The trolls were more clever and diverse than what you see now, but they also posted quite a bit more. It didn't ruin the conversation on Slashdot. I think most people would say that Slashdot in the early 2000s, when crapflooding was rampant, was also far better than Slashdot is now. Three things were primarily different:
1) Crapflooding accounts could post almost without limit on the number of posts, but those posts started at a score of -1. Anonymous posting had more restrictions, so many of the crapflooders logged in because it was the path of least resistance. The posts were already at -1, out of the way. Now, posting from crapflooding accounts is highly restricted, so anonymous posting at 0 is the path of least resistance.
2) Editors used unlimited mod points to suppress anonymous crapflooding, which was faster and more effective than relying on ordinary users to moderate. The editors now don't seem to mod down crapflooding nearly as much.
3) There were a lot more on-topic posts, and the volume of quality posts has markedly declined. Crapflooding didn't drive off those users, especially since there was more crapflooding in the past. Driving off crapflooders won't fix the problem. The focus should be on how to attract more quality posts rather than worry about how to drive off crapflooders.
By the way, your post is also off-topic and contributes to the noise by starting an entire thread. What, exactly, can Slashdot management tell you by email that will change the situation? It's a fair point that it'd be nice to see more posts from whipslash about his plans for Slashdot. But what exactly were you expecting him to tell you? Your suggestions are poorly thought out and your post comes across as petulant. Grow up.
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." ---
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.
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.