National Geographic: Hubble's Cosmic Journey

This is your window into the universe... Hubble was launched in April 1990 on board Space Shuttle Discovery. Its release into orbit over 500km above the Earth marked the birth of one of humanity's biggest dreams; to place a telescope into space, high above the obscuring effects of the atmosphere, to gain the clearest view of the cosmos we could hope to see. But in the months which followed it was clear that the dream had turned into a nightmare, as Hubble's mirror was found to have a flaw.