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Hubble Accuracy Surpassed By Earthbound Telescope
randuev writes "A high-speed adaptive optics system helped the Large Binocular Telescope (on Earth) to beat the accuracy of the Hubble Space Telescope's observations. 'A special sensor detects atmospheric distortions in real time and controls the mirror to adjust its position to compensate, effectively canceling out the blurring. The mirror can make adjustments every one-thousandth of a second, with accuracy to better than ten nanometers.' Now, that's what I call real-time. This nifty trick multiplied the Strehl ratio (optical quality) of the LBT by about 80 times. The new system was tested in May and June, so hopefully we'll soon see more space around us in higher resolution on Google Sky."
While this does mean that it could possibly make some Deep Field images. There is still another problem that makes this possibly intractable. The atmospheric absorption of some wavelengths means that it might still not be able to see certain areas in the spectrum effectively; this could prevent it from being able to produce nice deep field images like the hubble. However this ability to resolve objects that much better means that it could most certainly be effective at searching for planets.
Alas, there's no way around the Rayleigh criterion: http://en.wikipedia.org/wiki/Angular_resolution
We're not going to construct one-hundred-kilometer size telescopes any time soon.
It's great that atmospheric distortion can be largely eliminated, but just wait until we get some improved optics into space. Hubble has produced wonderful images, but the James Webb Space Telescope is going to be a phenomenal upgrade.
...that it was more than 20 years ahead of any Earth-bound telescope when it launched.
There are several limitations to adaptive optics, which are by no means a cutting edge technology for large observatories any more. Just about every telescope being built or upgraded today are having adaptive optics fitted.
One major limitation is that the adaptive optics are only good for small fields of view since you're using a single guide star to calibrate the disturbances in the atmosphere you're correcting. So they are not good for imaging multiple objects or even large single objects (like a single galaxy). Another is that since you're not in orbit like Hubble you have to wait for the planet to rotate, so a deep field would take much longer anyway.
When we lose Hubble we lose some unique capability. Even successor telescopes that don't work in optical light will not fill that void. Adaptive optics will only be useful in some circumstances whereas Hubble would have been useful in the general case. Oversimplifications like this story don't belong on a techy site like slashdot.
These posts express my own personal views, not those of my employer