400 Years of the Telescope: A Journey of Science, Technology and Thought is a 2009 American documentary film that was created to coincide with the International Year of Astronomy in 2009. Directed by Kris Koenig, it chronicles the history of the telescope from the time of Galileo and features interviews with leading astrophysicists and cosmologists from around the world, who explain concepts ranging from Galileo's first use of the telescope to view the moons of Jupiter, to the latest discoveries in space, including new ideas about life on other planets and dark energy, a mysterious vacuum energy that is accelerating the expansion of the universe.