Space telescope to maintain. The Hubble Space Telescope was serviced by the Space Shuttle while many other space telescopes cannot be serviced at all. Space observatories can generally be divided into two classes: missions which map the entire sky (surveys), and observatories which focus on selected astronomical objects or parts of the sky. Satellites have been launched and operated by NASA, ISRO, ESA, Japanese Space Agency and the Soviet space program later succeeded by Roskosmos of Russia. As of 2018, many space observatories have already completed their missions, while others continue operating on extended time. However, the availability of space telescopes and
Space Shuttle orbiter Space Shuttle orbiters were assembled at Rockwell's assembly facility in Palmdale, California, at the federally owned Plant 42 complex. In addition to the test articles and orbiters produced for use in the Shuttle program, there are also various mock-up replicas on display throughout the United States: Space Shuttle orbiter The Space Shuttle orbiter was the spaceplane component of the Space Shuttle, a partially reusable orbital spacecraft system that was part of the Space Shuttle program. Operated by NASA, the U.S. space agency, this vehicle could carry astronauts and payloads into low Earth orbit, perform in-space operations, then re-enter the atmosphere