This is the International Year of Astronomy, commemorating the 400th anniversary of Galileo’s first perusal of the sky with a small telescope. It is fitting that 2009 also marked the fifth and final Shuttle-based servicing mission (SM4) to the Hubble Space Telescope, the most influential astronomical telescope since Galileo’s. With the addition of two new cutting-edge scientific instruments, the repair of two other instruments and major maintenance of the spacecraft, SM4 brought the Hubble Observatory to the apex of its scientific capabilities, making it more capable than ever before. In this talk I’ll present a brief overview of the SM4/STS-125 mission, discuss the major gains in Hubble’s scientific performance, illustrate these with some examples of early scientific results, and reflect a bit on what the Hubble program has achieved in the course of the past two decades.