Hubble Space Telescope

Hubble is the first space-based observatory specifically designed for servicing while in orbit.
Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.
Throughout the history of science, revolutionary instruments propel our understanding with their landmark discoveries. The Hubble Space Telescope is a testament to that concept. Its design, technology and serviceability have made it one of NASA’s most transformative observatories. From determining the atmospheric composition of planets around other stars to discovering dark energy, Hubble has changed humanity’s understanding of the universe.
Overview
Before any commands can be sent to Hubble to tell it what astronomical targets to observe, those targets must first be identified and scheduled by the Space Telescope Science Institute in Baltimore, Maryland. The schedule of commands is then sent to the Space Telescope Operations Control Center (STOCC) at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, which operates and commands Hubble.
To communicate with Hubble, the STOCC utilizes NASA’s Space Network. This network consists of a constellation of satellites in geosynchronous orbit named the Tracking and Data Relay Satellites (TDRS) as well as the ground facilities that support and communicate with those satellites. Hubble commands are transmitted from the STOCC and routed through dedicated radio dishes at the White Sands Complex (a Space Network facility near White Sands, New Mexico) to the TDRS spacecraft and then to Hubble.