I can never understand how super duper great optics can beat a space based telescope since the atmosphere will never be perfectly still.
One would reckon that some dynamic algorithm can be used to compensate for the distortion but how does such a program know how much to compensate continuously?
Furthermore, many of the new ground based telescopes are no longer "purist". They don't seek to capture light and reproduce it in its purest form.
Rather, the input signals are aggressively processed to extract info of particular areas of interest instead.
Hubble should be saved but I ask how much is too much. US$1Bil seems really too excessive to send a robot to repair one camera and service the scope in general...especially when the Iraq is currently sapping all their resources.
Hubble is failing x.x
- Airconvent
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- carlogambino
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I used to feel the same way until i read more on adaptive optics and such... this "dynamic algorithm" is so good it can almost cancel out atmospheric distortion by vibrations and others, since there is minimal already, i think. (its on a mountain and probably near a dry place, like a desert). Anyway, I'm a hubble fan, so i'm still praying for it to be repaired.Airconvent wrote:I can never understand how super duper great optics can beat a space based telescope since the atmosphere will never be perfectly still.
One would reckon that some dynamic algorithm can be used to compensate for the distortion but how does such a program know how much to compensate continuously?
Furthermore, many of the new ground based telescopes are no longer "purist". They don't seek to capture light and reproduce it in its purest form.
Rather, the input signals are aggressively processed to extract info of particular areas of interest instead.
Hubble should be saved but I ask how much is too much. US$1Bil seems really too excessive to send a robot to repair one camera and service the scope in general...especially when the Iraq is currently sapping all their resources.
- weixing
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Hi,
Have a nice day.
Adaptive optics is not an algorithm... it actually change the surface of a deformable mirror to cancel out the distortion.One would reckon that some dynamic algorithm can be used to compensate for the distortion but how does such a program know how much to compensate continuously?
Have a nice day.
Yang Weixing
"The universe is composed mainly of hydrogen and ignorance." 


- carlogambino
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well... we just pray and hope that the hubble will be given a life line. anyway, looking from the surface of the earth is like trying to view things outside from within the pond(water medium as the atmosphere). while in space, it will be free of any distortions ... so... i still feel that the hubble telescope is indispensable.
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Think awhile about the benefits of ground-based telescopes.
You could have a big mirror for a ground-based telescope, whereas a space-borne telescope have to be small enough to fit in the shuttle bay.
Servicing is cheaper if it's on the ground. You don't need expensive shuttle missions, ie training of astronauts + training of support crew + risk involved (think Challlenger / Coloubia) + expensive hardware.
Adaptive optics and other new technologies can improve the images from ground-based telescopes until they rival that of HST. The trade-off is that you get the feeling the images are "artificial". But images has always been "artificial". The image depends on the formula of the emulsion of the film. Nowadays it depends on the CCD. Even different people have eyes that have different sensitivities. So what is "artificial", and what is original?
Look at the images in Singastro albums. How many of them have been edited? As in stacked or corrected for contrasts and brightness etc?
You could have a big mirror for a ground-based telescope, whereas a space-borne telescope have to be small enough to fit in the shuttle bay.
Servicing is cheaper if it's on the ground. You don't need expensive shuttle missions, ie training of astronauts + training of support crew + risk involved (think Challlenger / Coloubia) + expensive hardware.
Adaptive optics and other new technologies can improve the images from ground-based telescopes until they rival that of HST. The trade-off is that you get the feeling the images are "artificial". But images has always been "artificial". The image depends on the formula of the emulsion of the film. Nowadays it depends on the CCD. Even different people have eyes that have different sensitivities. So what is "artificial", and what is original?
Look at the images in Singastro albums. How many of them have been edited? As in stacked or corrected for contrasts and brightness etc?
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If anyone is interested in earth-based telescopes, do check out this link"http://www.eso.org/projects/owl/", the 'scope is still in design phase but there are a few spectacular high resolution renderings of what it may look like, check it out.
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On another note, I do believe that the Hubble program should have been retired long ago, it costs quite a significant amount of money and resources just to keep the already obsolete piece of equipment running.
Besides if you are interested in high altitude based 'scopes, check out SOFIA(Stratospheric Observatory For Infra-red Astronomy) at this link "http://sofia.arc.nasa.gov/". This 747 based scope would be significantly cheaper to maintain, easier to upgrade and if you have the money, you might also be able to take a ride with the crew.
I wonder when are they going to start planning for moon based observatories... ... ...
Besides if you are interested in high altitude based 'scopes, check out SOFIA(Stratospheric Observatory For Infra-red Astronomy) at this link "http://sofia.arc.nasa.gov/". This 747 based scope would be significantly cheaper to maintain, easier to upgrade and if you have the money, you might also be able to take a ride with the crew.
I wonder when are they going to start planning for moon based observatories... ... ...
- zong
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Moon based observatories? I think the scientists discussed about it before, but objections were many, because half the time the scopes would be facing a big ball of burning gas and unusable.. Also, we gotta think "get there and set up civilisation" before planning an observatory there.. How to support life first, before how to build scope there.