STS-125

STS-125
Mission	STS-125
Operator	NASA
Spacecraft	Space Shuttle Atlantis
Mission type	Servicing Mission to the Hubble Space Telescope
Launch date	11 May 2009
Landing date	24 May 2009
Duration	13 days, 18 hours, 6 minutes
Orbit low km	569
Orbit inclination deg	28.5

STS-125 STS-125 was the fifth and final dedicated servicing mission to the Hubble Space Telescope, flown by the Space Shuttle Atlantis under the auspices of NASA, the Johnson Space Center, and the Kennedy Space Center. The mission assembled experts from the Space Shuttle Program, Marshall Space Flight Center, and the Goddard Space Flight Center to perform upgrades and repairs originally envisioned during the era of the Hubble Space Telescope Key Project and the Hubble Deep Field investigations.

Mission overview

The mission objective was to install new instruments and replace failing systems on the Hubble Space Telescope to extend operational life for projects like the Cosmic Evolution Survey and investigations following discoveries such as the Hubble Ultra Deep Field and observations related to the Accelerating expansion of the universe. The flight plan drew upon lessons from the STS-61 servicing mission, coordination with the European Space Agency, and risk assessments updated after the Columbia disaster and recommendations from the Columbia Accident Investigation Board and the Presidential Commission on Implementation of United States Space Exploration Policy.

Crew

The seven-person crew included commander Scott D. Altman, pilot Gregory C. Johnson, and mission specialists Michael J. Massimino, Andrew J. Feustel, John M. Grunsfeld, Michael T. Good, and K. Megan McArthur. Crew training involved the Neutral Buoyancy Laboratory, simulations developed by the Johnson Space Center and technical collaboration with engineers from the Space Telescope Science Institute, Ball Aerospace, and the PerkinElmer Corporation teams who supported instrument development.

Payload and spacecraft

Atlantis was outfitted with the Hubble Space Telescope payload bay configuration, including the Wide Field Camera 3 (WFC3) built by Ball Aerospace, the Cosmic Origins Spectrograph (COS) produced with contributions from the Space Telescope Science Institute and European Space Agency partners, replacement Fine Guidance Sensors from Northrop Grumman, and a new Soft Capture Mechanism designed with input from the Godard Space Flight Center. The mission carried spare parts such as a replacement Gyroscope assembly, new Battery units, and a refurbished Space Telescope Imaging Spectrograph (STIS) to restore ultraviolet spectroscopy capabilities used in programs like the Mukaiyama–Masek observations and studies of exoplanet atmospheres.

Timeline and mission activities

After rollout at the Vehicle Assembly Building and processing at the Orbiter Processing Facility, Atlantis launched from Launch Complex 39A at the Kennedy Space Center on 11 May 2009. The rendezvous and grapple sequence used the shuttle's rendezvous radar and the Remote Manipulator System operated by mission specialists while coordinated with flight controllers at the Mission Control Center in Houston. The mission executed five planned Extravehicular Activity periods and numerous robotic operations to swap instruments, replace hardware, and perform comprehensive inspections informed by procedures developed with experts from the National Optical Astronomy Observatory and the Institute of Astronomy.

EVA (spacewalks)

Five EVAs were conducted by pairs of astronauts including Michael J. Massimino, John M. Grunsfeld, and Andrew J. Feustel to perform complex instrument swaps and servicing tasks originally modeled after techniques used during the STS-61 and later missions. Tasks included removal and installation of the WFC3 and COS, replacement of gyroscopes and batteries, removal and reattachment of thermal insulation, and a contingency repair of the STIS electronics module following diagnostics informed by the Space Telescope Imaging Spectrograph engineering teams. The EVAs relied on suits and procedures refined after the Hubble Servicing Mission 2 and the operational experience of astronauts from the International Space Station program.

Launch and landing

Launch occurred on 11 May 2009 from Kennedy Space Center Launch Complex 39A with post-launch operations managed by the Launch Control Center and trajectory analysis from JSC flight dynamics. Following completion of objectives and deorbit burn maneuvers coordinated with the Johnson Space Center and Cape Canaveral Air Force Station range safety, Atlantis touched down on 24 May 2009 at Kennedy Space Center Shuttle Landing Facility, concluding 197 orbits and a mission duration of 13 days, 18 hours, and 6 minutes.

Mission legacy and significance

The mission extended the operational lifetime of the Hubble Space Telescope, enabling subsequent discoveries related to dark energy studies such as those pursued by the Supernova Cosmology Project and the High-z Supernova Search Team, detailed imaging for programs like the Hubble Ultra Deep Field and exoplanet characterization that informed planning for the James Webb Space Telescope and future missions by NASA and the European Space Agency. The success of the servicing mission affirmed in-orbit repair capabilities championed by advocates including the National Academy of Sciences and influenced policies at the NASA Advisory Council regarding on-orbit maintenance and the design of servicing-compatible architectures for observatories and platforms such as the International Space Station and proposed missions by Northrop Grumman and Boeing. The mission is remembered in outreach and scholarly works curated by the Space Telescope Science Institute and featured in retrospectives produced by the Smithsonian National Air and Space Museum.

Category:Space Shuttle missions