Hubble Accuracy Surpassed By Earthbound Telescope 87
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."
Sounds good (Score:2, Interesting)
This doesn't mean we'll see better Deep Field images does it?
I know they used super new adaptive optics but it wont increase the amount
of light collected.
Better than the Hubble, but... (Score:5, Interesting)
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.
Re:Sounds good (Score:4, Interesting)
Probably not. It's not that the binary telescope isn't capable of doing Deep Field work, but the deepest of the deep imaging shots took Hubble keeping its optics focused on a single, apparently dark area of the sky for literally months. Deepest sky search took up most of the Hubble's lifespan during the last few years, and many other projects had to be put on the back burner. Administering big science involves trying to share time fairly for many projects, and I'd bet that many of the first time slots scheduled on the new version of the binary array are promised to the people who were bumped from the Hubble when it became apparent it was a good tool to investigate the very early universe. Other time is doubtless already reserved for those non-cosmologists who want to do other important astronomical things, such as exoplanet searches and resolving what's possible in visible wavelengths of our own galactic core. There's also a need sometimes to do visual backup observation when the orbiting infra-red or x-ray scopes find something unexpected in their wavelengths, and how much time could be borrowed or traded around for this depends on just how weird the other observations are.
Re:Impressive! (Score:3, Interesting)
Nope. Except for the basics, deblurring algorithms are usually highly application specific. The one you link to only handles motion blur caused by the camera moving and requires six axis motion tracking.
Before Hubble was repaired, a different, more general deblurring algorithm was used to help correct the distortion from the bad lens.
Although, many of the atmospheric distortion correction methods require a guide star. If no guide star is available one is created by shining a powerful laser up into the atmosphere. Such a laser might be handy to have on a cell phone.
Re:More please!!! (Score:4, Interesting)
: using the sun as a gravitational lens. Sure, it need a spacecraft to go 13x times farther than any spacecraft ever did, but we would get gorgeous pictures. Some people say this may be our only way to ever observe directly exo-planets in details. I am not sure if it enters in the "practical within my lifetime constraint" but if you have 50 more years to go, I wouldn't rule it out.
Re:Several limitations to Adaptive Optics (Score:3, Interesting)
That is why they build MCAO which means multi-conjugate adaptive optics, most often with laser guide stars. It allow for much greater isoplanatic field of view. This is done using (typically) three sensors and the adaptive mirrors projected to different heights in the atmosphere. I wouldn't say is a done deal but it's certainly quite far along and several telescopes are equipped with this stuff. I'm not sure how much real science has yet been done with this technology though but the improvements I've seen my self are very significant but I can't say right now if the Strehl ratio is above one half which I would consider really impressive.
Re:Several limitations to Adaptive Optics (Score:2, Interesting)
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.
What I don't understand is why we don't have a direct successor to Hubble. James Webb will be an infrared satellite, not visible light, so I don't see how it's a direct successor (IANAA I Am Not An Astrophysicist). I know of no other satellites that overlap but improve Hubble's coverage. Yes, I understand that today, adaptive optics beat Hubble, but Hubble was launched in 1990. Twenty years later the ground-based coverage bested space-based, but what could we conceivably learn from a visible-wavelength orbital observatory in the next 20 years before the ground-based ones catch up?
Beyond that, visible-light satellites have the capacity to excite the public like no others. Humans see the visible spectrum directly, and are just more impressed by visual wavelength images than false-color imagines of, say, X-rays. Non-visible wavelengths may be more scientifically important that visible ones, but the visible wavelengths are the ones that the public will pay for.