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 Surveillance Telescope Space Surveillance Telescope The Space Surveillance Telescope is a telescope for detecting and tracking orbital debris. It has a 3.5 meter (138″) aperture mirror and came online in 2011. Two noted design features include Mersenne-Schmidt type optics and a curved CCD. In 2010s the telescope, which was in New Mexico, United States, was transferred to United States Air Force Space Command and moved to Australia. The discovery and tracking of space debris is noted as a growing problem in the 21st century. One problem is that among the 20-30 thousand large objects in orbit that are tracked, and an estimated