Servicing Missions and New Instruments
Hubble was designed to accommodate regular servicing and equipment upgrades. Five servicing missions (SM 1, 2, 3A, 3B, and 4) were flown by NASA space shuttles, the first in December 1993 and the last in May 2009. Servicing missions were delicate operations that began with maneuvering to intercept the telescope in orbit and carefully retrieving it with the shuttle's mechanical arm. The necessary work was then carried out in multiple tethered spacewalks over a period of four to five days. After a visual inspection of the telescope, astronauts conducted repairs, replaced failed or degraded components, upgraded equipment, and installed new instruments. Once work was completed, the telescope was redeployed, typically after boosting to a higher orbit to address any orbital decay caused by atmospheric drag.
Read more about this topic: Hubble Space Telescope
Famous quotes containing the words missions and/or instruments:
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