The real future of telescopes will have no mirrors.
I'm not sure why no one has made a big deal out of this, but superconducting cameras have the potential to completely replace mirrors in telescopes, making them more robust and essentially eliminating complex alignment.
Why do I say this? Well, I reasoned this out myself, so maybe I'm wrong, but basically superconducting cameras are able to register every photon that sees them, sending off ~18000 electrons per photon hit. CCDs, on the other hand, send off 1 electron for every photon hit (I read that a while ago but I think those are the numbers).
Since CCD sensors are so much less sensitive, we use massive mirrors to magnify the amount of light hitting the sensor.
Well, it seems to me that if we had high resolution functional S-CAM sensors, we wouldn't need mirrors. We could just point them straight to the sky, and even if 18000 times fewer photons hit them, they'd have roughly the same or better output as a CCD.
Or, you could just lay out a giant array of S-CAM pixels, say, 10 meters in diameter. Then you'd basically have a ten meter telescope without the mirrors, *and* it would be vastly more sensitive.
I understand that using superconductors is currently an enormous pain in the ass, and I'm not expecting us to find a room-temp one any time soon, but even with the complexities of keeping the sensor cool, wouldn't that have enough advantages over a traditional system that it might be worth it? Maybe not yet, as the sensors currently have to be 0.3K, which seems to me to make it extremely challenging. But if we could make them with something warmer - say, liquid nitrogen cooled - then they might be viable.
Is there any flaw in my basic reasoning? I mean, maybe it would be more expensive than I imagine, but I feel like we should be looking into it. Imagine a football-field sized array of S-CAM sensors. I feel like we could pretty much see license plates on alien worlds at that point. And it wouldn't be nearly as fragile as something with a mirror.
http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=36685
That is the third generation superconducting camera sensor that the ESA is working on. It only has 120 pixels, but I really believe we should be putting way more money into researching these...
-Taylor