Hubble’s corrective lens
Following the Space Shuttle repair mission to the Hubble Space Telescope, the orbiting telescope’s new Wide Field and Planetary Camera 2 shows incredible improvement in image resolution. By determining the exact deformation of the telescope’s main mirror, the new camera is created almost like corrective glasses: it’s designed to compensate for that deformation at all times. The resulting improvement in image quality is remarkable, enabling Hubble to spot volcanic activity on Io, a moon of Jupiter whose volcanoes have only been visible from space probes making a close flyby. Hubble’s improved vision also arrives just in time to witness an unprecedented event: a cometary collision with Jupiter later in 1994.