CSPAN2 Book TV August 20, 2011
have a pair of telescopes separated by 22 meters in the case of large binocular telescope scum i you can essentially get an image of a crosscut and what you're able to do is take advantage of the earth's rotation and to rotate the pair of telescopes to a variety of angles to build up a whole series of cross sections to reconstruct images from those separate cross-section spirit of that is how you do it and trying to give a variety of angular resolution and sensitivity, the structures in different sizes is number one. number two, making use of the earth's rotation you could get many, ...