Hey folks, I've had a weird idea bouncing around in my head, and I'm pretty sure it's not possible, but I wanted to get some more input.

With the recent advances in interferometry, is there any way that many smaller telescopes could be linked together similar to the Gemini observatories? From what I understand, you have to have very precise positioning between the individual instruments, and you also require a tremendous amount of computer processing power to combine the data. Could there be a way that individuals could link up their telescopes, and other volunteers could lend computing time to process the various images to produce a single high-resolution image? I guess I'm thinking of something like SETI@home. Is that completely impossible, or just super unfeasible? Would something like this be limited to only the brightest objects, like the Sun, moon, etc, because of atmospheric disturbence?

If someone could kill this idea, I'd appreciate it. I need it out of my head.

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Disclaimer: I'm not really an expert on this. But...

I believe that it might be possible to set up an amateur interferometry network for radio astronomy. It should be possible to record the data at two distant locations, along with a highly accurate timebase signal, and combine the results later. This is because of the relatively long wavelengths of radio signals. However, the cost of the timebases might be prohibitive for amateurs (we're talking atomic-clock accuracy here). And there's the problem of properly synchronizing those clocks. And while there are amateur radio astronomers, they're far fewer than optical stargazers.

My understanding is that this technique doesn't work for optical astronomy. The wavelengths are many orders of magnitude shorter (meters or centimeters vs. angstroms!), so the requirements of the timebase are accordingly stricter. As far as I know, the only attempts to do optical interferometry (so far) involve direct optical paths to allow the interference to take place in real time. That is, the light from scope A and that from scope B are directed to a common place and combined, not recorded and combined later by post-processing.

Oh, and pardon my manners... welcome to the BABB, UT... 8)

Hey UT. If Donnie B.'s valid comments haven't gotten that idea "out of your head" yet, a bit of reading at "www.iram.es/IRAMFR/IS/html_2/node27.html" should. The use of adaptive optics (to counter the effects of atmospheric turbulence on optical wavelengths) is pretty much mandated, with the associated non-amateur investment required.

Still, sometimes those pesky amateurs don't know the meaning of "no", and may find a way around the established technology.

Cheers. Newt.

Welcome! To make interferometry work, you need to know the relative positions of the scopes with an accuracy comparable to the wavelength you're observing. This makes it pretty easy to do for radio, but for visible light, that means that you need precision of a few hundred nanometers. I don't think they're actually doing that even with the Gemini scopes, they're just identical telescopes placed so that one has a view of the northern sky and the other has a view of the southern, so the data will be comparable. That's another issue, that for interferometry to work, you really need to have all of the instruments involved be identical; it would be too complex to try to account for the difference mathematically. There are telescopes that have been set up for visual interferometry, like the twin Keck scopes, VLTI, CHARA, COAST, IOTA, and NPOI. NPOI recently managed to link six telescopes. It's quite a feat of engineering to do that even with these scopes that were designed for it, and it's way beyond the practical capabilities of amateur astronomers.

I have an idea that I don't know if it's feasible..

Instead of inferometry, just have millions of people taking pictures of the night sky with their digital cameras without clouds. They can send the pictures in and then sophisticated computations could take the sum of all those pictures and resolve the entire night sky.

Of course if you took 1000 pictures of the sky from the exact same position you wouldn't be able to derive any further resolution from it than the resolution of the camera -- but every camera's disposition, the disposition of its pixel boundaries relative to the sky, will be unique. Software could determine the precise disposition of each picture based on which pixels are lit up how much by which stars, and then by making one huge grid of all the pixel values with their respective boundaries, it could interpolate a very fine resolution.

Of course before it even determines the pixel offset it has to determine the general orientation which can be done by matching the image with a reference. Also, to account for parallax, users need to send in the info of where they're located and at what time they took each picture.

Perhaps instead of just taking pictures of the sky people can take pictures with their telescopes, but that requires finding the exact position to point to that the project is currently looking at. But that may be the only feasible way of doing it if any. But I think people would have to go out and buy telescopes that can take digital pictures.