At a ceremony held today at the National Federation of the Blind, NASA unveiled a new book that brings majestic images taken by its Great Observatories to the fingertips of the blind. The Great Observatories include NASA's Hubble, Chandra and Spitzer space telescopes. "Touch the Invisible Sky" is a 60-page book with colour images of nebulae, stars, galaxies and some of the telescopes that captured the original pictures. Each image is embossed with lines, bumps and other textures.