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Multiple space telescopes inter-coordinated?


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I don't remember what magazine, perhaps Discover (a while back), the article said NASA planned to have giant telescopes arranged in a system where each is many kilometers away from the others, with their lens perfectly aligned to create a fantastically large magnification (because of the distance apart).

 

The other thing I remember is a scientist's claim that if aliens did exist on a planet, with this you'd be able to see the white of their eyes.

 

Anyone familiar with the article, or the concept, plan, whatever?

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you wouldn't get that kind of focus out of anything. doesn't matter how big it is.

 

there are satellite based telescopes that work in multiples though. the stereo sattelites observe the sun to obtain a pseudo-3D view.

 

there are plans for future space based arrays as well but none of them will be able to directly spot life on planets multiple light years away. we might catch a glimpse of their planet though.

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you don't need multiple telescopes for that. we can make distance measurements to stars by taking andle measurements at 6 month intervals(when the earth is on the other side of the sun) and the direction of this distance is achieved by looking at which way we point the telescope to observe it.

 

we already have a 3-D map of the universe and the proper velocity of most nearby stars. more distant stars are more difficult to get a proper velocity for but this is easily solved by waiting a decade or two and remeasuring.

 

a big space based array would certainly help by allowing use to survey more stars at once, but it is by no means necessary to the success of such a project. it would also be cheaper to build even more ground based radio telescopes for this purpose. space based telescopes are primarily to avoid distortion and absorbtion of certain wavelengths by our atmosphere.

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This would be an Interferometer telescope. These sum the light from multiple individual telescopes linked together in a very precise manner to act as if it is a telescope of a much larger size.

 

Here is the Wikipedia article about interferometers to get you started: http://en.wikipedia.org/wiki/Interferometry#Astronomical_interferometry

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i don't think so ..........and how can you be sure about aliens are big ( evolved ) . there is good probability that they are only in the stage of development like unicellular ( or less) , and why should we take them as the intelligent enough to show there presence in the space ............

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there is good probability that they are only in the stage of development like unicellular ( or less) , and why should we take them as the intelligent enough to show there presence in the space ............

 

I think that that really depends on the age of the planet amongst other things, and if I'm not mistaken there is a good probability that there are old enough planets in the Milky Way to harbour intelligent life. But let's not hijack the thread.

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http://www.astro.lsa.umich.edu/~monnier/Publications/ROP2003_final.pdf

 

This is a very informative paper on optical interferometry. Chapter 5 deals with the near future and mentions resolutions below 0.1 milliarcseconds. Interferometry also involves coronagraphs that "turn off" the light of a star by interphasing the peak and trough of its lightwave to cancel it out entirely.This "nulling" allows the weaker light of nearby planets to be resolved more easily. Software, supercomputers and shere numbers count too, as ten interconnected telescopes are better than six, etc.

What might HAL 9000 do with a dozen Thirty Meter Telescopes?

 

http://en.wikipedia.org/wiki/Thirty_Meter_Telescope

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Google the term "telescope array". Let me do that for you: http://lmgtfy.com/?q=telescope+array.

Ha!, awesome link :)

 

Yet I didn't find the relevant stuff in Google, but found it using my trusty IxQuick search engine of choice. Look at their excellent Privacy notice higlighted in the circle, and you'll see why I continue to use it. ;)

 

Anyhow, your keyword lead and Edtharan's suggestion helped me find close to what I needed.

 

This would be an Interferometer telescope. These sum the light from multiple individual telescopes linked together in a very precise manner to act as if it is a telescope of a much larger size.

Here's what I found looking it up.

 

http://blogs.discovermagazine.com/badastronomy/2009/02/18/wonder-twins-telescope-sees-stars-dying-gasps

 

The image above is not an illustration, it’s an actual image of a red giant star undergoing dying paroxysms and blasting a dense shell of molecules into space

.....

This incredible picture was not taken by a single telescope. It was produced by combining the light of four different 1.8 meter telescopes in a process called interferometry. It’s a fiendishly complex process that virtually creates a telescope that has the same resolution (ability to see small objects) as a single telescope spanning the separation between the smaller ones. In other words, separate the smaller ’scopes by 100 meters, and you can create a virtual telescope 100 meters across.

 

The longer the wavelength, the easier this process is (though it’s never easy); in this case the image was taken in the infrared. It took multiple observing sessions over several nights, but in the end the astronomers were able to see objects as small as two milliarcseconds across– much smaller than Hubble can resolve, and equivalent to an object just four meters across sitting on the Moon’s surface!

 

The image referred to...

 

tlep_vlt.jpg

 

 

A related link.

 

http://www.skatelescope.org/pages/page_genpub.htm

 

An initiative has emerged to develop a telescope to provide two orders of magnitude increase in sensitivity over existing facilities at metre to centimetre wavelengths. To achieve this goal will require a telescope with one square kilometre of collecting area - one hundred times more collecting area than the Very Large Array (VLA).

.....

The SKA will be an interferometric array of individual antenna stations, synthesizing an aperture with diameter of up to several 1000 kilometers. A number of configurations are under consideration to distribute the 1 million square metres of collecting area. These include 30 stations each with the collecting area equivalent to a 200 metres diameter telescope, and 150 stations each with the collecting area of a 90 m telescope

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http://www.astro.lsa.umich.edu/~monnier/Publications/ROP2003_final.pdf

 

This is a very informative paper on optical interferometry. Chapter 5 deals with the near future and mentions resolutions below 0.1 milliarcseconds.

Wow, that resolution can see an object just eight inches across on the moon. :)

 

(?) If my calculations aren't off.

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