In this photo, engineers in a clean room examine the actuators that will control one of the 18 mirror segments on the James Webb Space Telescope, the Hubble's successor. The actuators are small motors attached to a delta frame that will move the 55-pound mirror pieces an almost-inscrutable 7 nanometers at a time.
The JWST is so large that its primary mirror must unfold in space, and engineers have to be able to align each piece to form one smooth surface. Each mirror moves on three axes, and must function at roughly -400 degrees Fahrenheit -- the JWST is an infrared telescope, so its mirrors must be freezing cold to work well. Ball is a subcontractor of Northrop Grumman Aerospace Systems on the JWST.