NASA’s free interactive e-book for iPad, called Hubble Space Telescope Discoveries. Featuring stunning images, animations and videos by Hubble space telescope, about the amazing universe we live in.
“Soar through the universe with the Hubble Space Telescope, exploring discoveries from dark energy to colliding galaxies. This highly interactive eBook features video, image galleries and more to reveal the record of scientific breakthroughs behind Hubble’s stunning images of the cosmos.”
For iPad the book is available here (almost 900 MB)