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Ground-based Telescope as Sharp as Hubble
Midnight Thunder writes: "The BBC has an article describing how the Paranal Observatory has been able to take images that are just as sharp as the Hubble Space Telescope. For a ground based telescope the images are of amazing quality."
a funhouse!
It's interesting to note that the Paranal telescope modifies the mirror to correct for an imperfect lens (the atmosphere), while the Hubble has a corrective lens (installed in orbit) in it's system to correct for a manufacturing error in the mirror.
It makes me wonder if the Hubble would have been significantly better than Paranal if the mirror had been made correctly in the first place.
Liquor
Sanity is a highly overrated commodity.
If it wasn't for a grassroot congressmen, the hubble would have much much better clarity (its only producing something like 60% of what it could be).
This is enormous news when you consider the bottleneck of time the Hubble Space Telescope has become. If it works well, you can expect this technology to be applied to many ground-based observatories.
Then multiply it with the technology that merges the images from several mirrors to act like one giant mirror.
Finally, when you match this technology with the new technique devised to detect the atmospheres of distant planets, it really offers a lot to planet hunters.
I think this will revolutionize planet hunting, and bring the detection of Earth-sized planets with oxygen atmospheres within the near future.
Fraser Cain
Publisher, Universe Today - http://www.universetoday.com
Amateurs are doing amazing stuff. Here's an image of Saturn taken with an amateur 13-inch scope and a camcorder. It's compared side-to-side with a similar HST image. You will be surprised.
Dozens of amateurs joined in a program to supply images to the 2001 International Marswatch program during this past Martian observing season. The pros use these images to decide when to spend their valuable HST time to look at Mars. Some of the images (and visual drawings) are incredible.
IANAA, but I have a few comments neverthe less :)
First of all, visible light just isn't the best spectrum to do astronomy in for a lot of things, especially not the detection of extrasolar planets. Infrared radiation, unhindered by most space dust, and lower in energy, is clearly superior for studying things that are not giant balls of gas. The Next Generation Space Telescope and the Terrestrial Planet Finder both use infrared radiation to study objects of great interest that are difficult to study with something like the HST.
Interferometry, the technology you refer to that allows telescopes to combine their phase information to generate an image with angular resolution of that of a single larger telescope (through something known as apature synthesis) is only one of the many uses of intereferometry. Perhaps much more exciting than that is the ability of the Terrestrial Planet Finder to use nulling interferometry to selectively block out the radiation from a star, without blocking out the much fainter (millions of times less) glow of a circling planet.
Unfortunately the earth's atmosphere is mostly opaque to infra-red light, and room temperature objects (like most of the surface of the earth, and the telescopes on it) generate so much infra-red radiation that it makes it nearly impossible to do any far-infrared studies from the ground. The Darwin Project web site has a good explaination about the reasons terrestrial planet hunting should be done in space.
Ground based observatories will always have a place, however eventually it will be a matter of cost and convenience rather than any technical superiority.
Not saying this isn't cool, but it's mostly postponing the inevitable day when very little new astronomy can be done inside the confines of an atmosphere....
Aparently hubble which exists in space was so powerful at the time that it was put up there and it has the advantage that it does not have to go throuht the atmosperic distortion. However this new one is built on a mountain and is more powerful (newer technology) and is able to 'see' black holes at the center of galaxies. It seems that all galaxies have black holes, but not all black holes are feeding too. Of course the one at the center of our galaxy is feeding again... but don't worry, it wont eat us, at least not until after the andromedia galaxy collides with the milkyway in a few million years...
Only 'flamers' flame!
Keck's been capable of "beating" Hubble for a good long while now. Adaptive Optics is wild and crazy stuff.
Please don't believe that we'll be able to do away with space-based observing because of this innovation. Our atmosphere absorbs an awful lot of interesting wavelengths.
What we're observing is technical "stair-stepping."
At the time Hubble was conceived, ground telescope technology had run into a brick wall, specifically, atmospheric distortion. The solution? Well, fly above the atmosphere, and that's how Hubble was born.
25+ years since the era in which Hubble was designed, we now see that computers, optics, and control mechanisms have advanced to near-Asimov proportions - this has produced the ability to make a mirror that can compensate for the earth's atmosphere and optically eliminate its effects. So now, the Paranal facility (Keck, and others) can claim optical superiority over Hubble.
The next step, of course, is to apply similar anti-distortion and image linking techniques to a spaceborne observatory. Call this "Hubble 2" (or "Son of Hubble," "Hubble TNG," "Hubble AOTC," whatever fits).
The issue of image perfection and space orbservatories is a matter of economics - it's always tougher to build things to go into space rather than similar ground-based systems, and so Hubble 2 might be a long time coming. When it arrives, though, Paranal will just seem like chaffe.
Nice shot for a home telescope but it's a small fraction of the resolution on the instrument you chose to compare with, and it can't match the capability of the other instruments on the Hubble. It's downright misleading to draw this comparrison.
Saturn is the easiest object to image, you chose it for a reason. How about some of the feinter objects. Come on show us just how incapable your 13 inch telescope really is with a deep field shot.
that the two sky images are reversed in the article?