Hubble Space Telescope’s 20th Anniversary

Top astronomers who have worked on the Hubble Space Telescope over the past 20 years talk about their major discoveries that were made possible only with a spaceborne observatory. The 12-minute look at Hubble’s top findings includes: galaxy evolution, dark matter, the age of the universe, black holes, extrasolar planets, and dark energy. Credit: NASA and M. Estacion (STScI)