To commemorate Chandra's ten years in orbit, a new trailer has been produced to spotlight NASA's premier X-ray telescope. This short video begins with Galileo some 400 years ago and brings the viewer to modern astronomy, of which Chandra's high-energy Universe plays a critical role. Transcript: In Florence, Italy, in the year 1609, the world changed. Using a small telescope, Galileo proved that the Earth is not distinct from the universe, but part of it. And he showed that there is much more to the universe than we see with the naked eye. In the twentieth century, astronomers made another revolutionary discovery - that optical telescopes reveal only a portion of the universe. Telescopes sensitive to invisible wavelengths of light have detected microwave radiation from the Big Bang, infrared radiation from proto-planetary disks around stars, and X-rays from explosions produce by black holes. Ten years ago this July, the most powerful X-ray telescope ever made began its exploration of the hot Universe. Explore the Universe with Chandra.