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
Spitzer Space Telescope open to the general public. The contest led to the telescope being named in honor of astronomer Lyman Spitzer, who had promoted the concept of space telescopes in the 1940s. Spitzer wrote a 1946 report for RAND Corporation describing the advantages of an extraterrestrial observatory and how it could be realized with available or upcoming technology. He has been cited for his pioneering contributions to rocketry and astronomy, as well as "his vision and leadership in articulating the advantages and benefits to be realized from the Space Telescope Program." The "Spitzer" was launched on 25 August 2003 at 05:35:39 UTC