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30 Years Ago: STS-61, the First Hubble Servicing Mission


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“Trying to do stellar observations from Earth is like trying to do birdwatching from the bottom of a lake.”  James B. Odom, Hubble Program Manager 1983-1990.

The discovery after its launch that the Hubble Space Telescope’s primary mirror suffered from a flaw disappointed scientists who could not obtain the sharp images they had expected. But thanks to the Hubble’s built-in feature of on-orbit servicing, NASA devised a plan to correct the telescope’s optics during the first planned repair mission. The agency assigned one of its most experienced crews to undertake the complex tasks, naming Richard O. Covey, Kenneth D. Bowersox, Kathryn C. Thornton, Claude Nicollier of the European Space Agency, Jeffrey A. Hoffman, F. Story Musgrave, and Thomas D. Akers to the STS-61 first Hubble Servicing Mission. The first all veteran crew since the STS-26 return to flight mission in 1988 had a cumulative 16 previous missions among them and all had previous spacewalking experience. During their 11-day flight in December 1993, they repaired the telescope during an unprecedented five spacewalks in a single space shuttle mission, rendering it more capable than originally designed.

The STS-61 crew of Kenneth D. Bowersox, sitting left, Kathryn C. Thornton, F. Story Musgrave, and Claude Nicollier of the European Space Agency; Richard O. Covey, standing left, Jeffrey A. Hoffman, and Thomas D. Akers The STS-61 crew patch Endeavour rolls over from Launch Pad 39A to 39B at NASA’s Kennedy Space Center in Florida
Left: The STS-61 crew of Kenneth D. Bowersox, sitting left, Kathryn C. Thornton, F. Story Musgrave, and Claude Nicollier of the European Space Agency; Richard O. Covey, standing left, Jeffrey A. Hoffman, and Thomas D. Akers. Middle: The STS-61 crew patch. Right: Endeavour rolls over from Launch Pad 39A to 39B at NASA’s Kennedy Space Center in Florida.

The first Hubble servicing mission proved to be one of the most complex up to that time. With that in mind, on March 16, 1992, NASA named Musgrave, an astronaut since 1967 and a veteran of four previous missions including conducting the first spacewalk of the shuttle era, as the payload commander and one of the four spacewalkers for STS-61. On Aug. 28, NASA named Hoffman, Akers, and Thornton as the other three spacewalkers who in teams of two would carry out the five spacewalks on alternating days. Finally, on Dec. 3, NASA named Covey, Bowersox, and Nicollier as the commander, pilot, and flight engineer, respectively, for the mission. Nicollier also served as the prime operator of the Remote Manipulator System (RMS), or robotic arm, with Bowersox as his backup. The seven-person crew trained intensely for the next year preparing for the complex tasks ahead, including simulating the spacewalks at the Neutral Buoyancy Simulator at NASA’s Marshall Space Flight Center in Huntsville, Alabama, and the Weightless Environment Training Facility at NASA’s Johnson Space Center in Houston. Meanwhile, at NASA’s Kennedy Space Center in Florida, workers prepared space shuttle Endeavour for its fifth journey into space. They rolled the shuttle, assembled with its external tank and solid rocket booster, to Launch Pad 39A on Oct. 28. However, following a wind storm on Oct. 30 that contaminated the payload changeout room with sandy grit, managers decided to move Endeavour to neighboring Pad B on Nov. 15, in only the second roll around in shuttle history.

Schematic of the Hubble Space Telescope’s major components Workers inspect the Hubble Space Telescope’s 94-inch diameter primary mirror prior to assembly Astronauts release the Hubble Space Telescope in April 1990 during the STS-31 mission
Left: Schematic of the Hubble Space Telescope’s major components. Middle: Workers inspect the Hubble Space Telescope’s 94-inch diameter primary mirror prior to assembly. Right: Astronauts release the Hubble Space Telescope in April 1990 during the STS-31 mission.

The first concrete plan for placing an optical telescope in space, above the obscuring and distorting effects of the Earth’s atmosphere, originated with Princeton University astronomer Lyman S. Spitzer in 1946. In 1972, NASA first proposed a plan to launch a Large Space Telescope (LST) and five years later Congress approved the funding. As envisioned, the LST would contain a 94-inch diameter primary mirror and launch on the space shuttle, then still under development, in 1983. With an expected on-orbit lifetime of 15 years, the LST’s instruments would make observations primarily in the visible and ultraviolet parts of the electromagnetic spectrum. In 1983, managers abandoned the original plan to use the space shuttle to return the telescope to Earth for refurbishment and relaunch in favor of in-orbit maintenance and upgrades by astronauts during spacewalks in the shuttle’s payload bay. The same year, NASA renamed the LST after astronomer Edwin P. Hubble and set the launch for October 1986. The Challenger accident in January 1986 delayed the launch of the Hubble Space Telescope until April 24, 1990, during Discovery’s STS-31 mission. The shuttle flew to an unusually high 380-mile orbit to ensure that Hubble would operate above as much of the Earth’s atmosphere as possible. After initial on-orbit activation and checkout of the telescope’s systems, it was time for the much-anticipated “first light” images. The initial images, however, puzzled scientists as they showed stars not as single well-focused points of light but as blurred and fuzzy. Investigators learned that the telescope’s primary mirror suffered from a production error, its edges too flat by 0.003 mm, resulting in an optical problem called spherical aberration. While this significantly degraded the capability of several of Hubble’s instruments to return exceptionally detailed photographs, the telescope still produced some good images. NASA put in place a plan to fix the Hubble’s optical problems without resorting to repairing the mirror. With the spherical aberration well-defined, engineers designed a set of mirrors that astronauts could place aboard Hubble during the previously planned first servicing mission.

Liftoff of space shuttle Endeavour on the STS-61 mission to repair the Hubble Space Telescope The Hubble Space Telescope as seen from Endeavour during the rendezvous, with the end of the Remote Manipulator System (RMS), or robotic arm, visible at lower right On the shuttle’s flight deck, European Space Agency astronaut Claude Nicollier operates the RMS to grapple Hubble
Left: Liftoff of space shuttle Endeavour on the STS-61 mission to repair the Hubble Space Telescope. Middle: The Hubble Space Telescope as seen from Endeavour during the rendezvous, with the end of the Remote Manipulator System (RMS), or robotic arm, visible at lower right. Right: On the shuttle’s flight deck, European Space Agency astronaut Claude Nicollier operates the RMS to grapple Hubble.

Planning for the first servicing mission to Hubble began in 1988, two years before the launch of the telescope. With the post-launch discovery of spherical aberration, the scope of the first servicing mission changed dramatically. The primary goal now focused on correcting the telescope’s optics to ensure that its onboard instruments could function as planned. Engineers developed the Corrective Optics Space telescope Axial Replacement (COSTAR), a tool to correct Hubble’s blurry vision, consisting of five pairs of corrective mirrors placed in front of the Faint Object Camera, the Faint Object Spectrograph, and the Goddard High Resolution Spectrograph (GHRS) instruments. Installing COSTAR required the removal of the High-Speed Photometer, the sacrifice of one instrument outweighed by the saving of the other three. The astronauts also replaced the original Wide Field Planetary Camera (WFPC) with the more advanced WFPC2 to improve the telescope’s ultraviolet performance. The WFPC2 carried its own corrective optics. The astronauts also replaced fuses and the telescope’s two solar arrays, one of which imparted vibrations that prevented precise pointing. On Dec. 2, 1993, space shuttle Endeavour lifted off from Pad 39B at 4:27 a.m. EST, after a one-day weather delay. Following insertion into an unusually high 360-mile orbit to reach Hubble, the astronauts began their initial on-orbit operations by opening the payload bay doors. The next day, Covey and Bowersox performed several engine burns as part of the rendezvous maneuvers. The astronauts checked out the rendezvous radar, the Ku-band antenna, the Canadian-built Remote Manipulator System (RMS) or robotic arm, and the spacesuits, and reduced the pressure inside the shuttle from 14.7 pounds per square inch (psi) to 10.2 psi in preparation for the upcoming spacewalks to reduce the pre-breathe time required to prevent decompression sickness or the bends.

Endeavour approach to the Hubble Space Telescope Hubble secured onto its flight support structure in Endeavour’s payload bay The STS-61 crew poses on Endeavour’s flight deck, with Hubble visible through the windows
Left: Endeavour continues its approach to the Hubble Space Telescope. Middle: Hubble secured onto its flight support structure in Endeavour’s payload bay. Right: The STS-61 crew poses on Endeavour’s flight deck, with Hubble visible through the windows.

On the third day, Covey brought Endeavour to within 30 feet of Hubble so Nicollier could grapple it with the RMS. Covey radioed Houston, “Endeavour has a firm handshake with Mr. Hubble’s telescope.” Nicollier berthed the giant telescope onto its turntable-like Flight Support System (FSS) in the shuttle’s payload bay. Nicollier then used the RMS cameras to perform an inspection of Hubble.

European Space Agency astronaut Claude Nicollier operates the shuttle’s Remote Manipulator System (RMS) or robotic arm in support of the spacewalks Astronaut F. Story Musgrave works on the Hubble Musgrave releases bolts on the replacement solar arrays
First spacewalk. Left: European Space Agency astronaut Claude Nicollier operates the shuttle’s Remote Manipulator System (RMS) or robotic arm in support of the spacewalks. Middle: Astronaut F. Story Musgrave works on the Hubble. Right: Near the end of the first spacewalk, Musgrave releases bolts on the replacement solar arrays.

With Nicollier operating the RMS as he did for all five spacewalks, Hoffman and Musgrave conducted the mission’s first excursion on flight day four. They replaced two sets of Rate Sensing Units that contain gyroscopes to orient the telescope and replaced electrical control units and fuse plugs, providing the telescope with six healthy gyroscopes. Musgrave and Hoffman prepared for the next day’s spacewalk by loosening bolts on the replacement solar arrays, stored in the forward part of the payload bay. The pair spent 7 hours and 54 minutes outside on this first spacewalk. The ground commanded the two existing solar arrays on the telescope to retract, and while one did so the second one did not due to a bent support rod.

Astronaut Kathryn C. Thornton, on the end of the Remote Manipulator System, releases Hubble’s old solar array that failed to retract properly The solar array drifting away from space shuttle Endeavour Thornton disconnects Hubble’s retracted solar array
Second spacewalk. Left: Astronaut Kathryn C. Thornton, on the end of the Remote Manipulator System, releases Hubble’s old solar array that failed to retract properly. Middle: The solar array drifting away from space shuttle Endeavour. Right: Thornton disconnects Hubble’s retracted solar array.

On flight day five, Thornton and Akers stepped outside for the mission’s second spacewalk, lasting 6 hours 36 minutes. The primary tasks revolved around replacing the telescope’s two solar arrays. First, they disconnected the array that would not retract as planned, working only at night since the array generated electricity when exposed to sunlight. With Thornton on the end of the RMS, she released the partially open array as Nicollier pulled her away. Bowersox fired thrusters to separate from the array, the plumes impinging on it causing it to flap like a giant bird. Thornton and Akers then connected one of the new arrays, rotated the telescope on its FSS, disconnected the other array, stowing it in the payload bay for return to Earth, and replaced it with a new one.

Astronauts Jeffrey A. Hoffman, left, and F. Story Musgrave have removed the old Wide Field Planetary Camera (WFPC) from Hubble, the black rectangle at upper left shows its former location With European Space Agency astronaut Claude Nicollier operating the Remote Manipulator System from inside the shuttle, Hoffman guides the new WFPC2 into position, with Musgrave ready to assist Musgrave, left, and Hoffman have installed WFPC2, the white triangle in the middle of the telescope, with Hoffman about to pick up WFPC1 temporarily stowed on the side of the payload bay and place it in its permanent location for return to Earth
Third spacewalk. Left: Astronauts Jeffrey A. Hoffman, left, and F. Story Musgrave have removed the old Wide Field Planetary Camera (WFPC) from Hubble, the black rectangle at upper left shows its former location. Middle: With European Space Agency astronaut Claude Nicollier operating the Remote Manipulator System from inside the shuttle, Hoffman guides the new WFPC2 into position, with Musgrave ready to assist. Right: Musgrave, left, and Hoffman have installed WFPC2, the white triangle in the middle of the telescope, with Hoffman about to pick up WFPC1 temporarily stowed on the side of the payload bay and place it in its permanent location for return to Earth.

On the sixth day, Hoffman and Musgrave took their turn outside for the mission’s third spacewalk. Their primary task involved the replacement of the original WFPC with the more advance WFPC2 instrument. With Nicollier controlling the RMS, Hoffman removed the WFPC1 from the telescope and temporarily stowed it on the side of the payload bay. He then removed WFPC2 from its stowage location and he and Musgrave installed it into the telescope. After stowing WFPC1 in the payload bay for return to Earth, Hoffman replaced two magnetometers, essentially compasses the telescope uses to determine its orientation in space. This third spacewalk lasted 6 hours 47 minutes.

Astronaut Kathryn C. Thornton works in shuttle Endeavour’s payload bay European Space Agency astronaut Claude Nicollier controlling the Remote Manipulator System, Thornton, top, removes the Corrective Optics Space telescope Axial Replacement (COSTAR) from its storage location Astronaut Thomas D. Akers, inside the Hubble Space Telescope prepares to install the COSTAR
Fourth spacewalk. Left: Astronaut Kathryn C. Thornton works in shuttle Endeavour’s payload bay. Middle: With European Space Agency astronaut Claude Nicollier controlling the Remote Manipulator System, Thornton, top, removes the Corrective Optics Space telescope Axial Replacement (COSTAR) from its storage location. Right: Astronaut Thomas D. Akers, inside the Hubble Space Telescope prepares to install the COSTAR.

For Akers and Thornton, the primary tasks of the fourth spacewalk on the mission’s seventh day focused on the removal of the HSP instrument and replacing it with the COSTAR system to correct the telescope’s optics. Akers opened the telescope’s shroud doors and with Thornton removed the HSP, temporarily stowing it on the side of the payload bay. Nicollier then maneuvered the RMS with Thornton to pick up COSTAR from its storage location and translate them to Hubble where Akers awaited to help with the installation. After closing the door and stowing the HSP, and installing an electronics package with additional computer memory, Akers and Thornton finished the 6-hour 50-minut spacewalk.

Remote Manipulator System operator European Space Agency astronaut Claude Nicollier translates Jeffrey A. Hoffman and F. Story Musgrave to the top of the Hubble Space Telescope The second of two solar arrays unfurls as Hoffman and Musgrave continue working Hoffman celebrates the first Hannukah in space, with a spinning dreidel floating nearby
Fifth spacewalk. Left: Remote Manipulator System operator European Space Agency astronaut Claude Nicollier translates Jeffrey A. Hoffman and F. Story Musgrave to the top of the Hubble Space Telescope. Middle: The second of two solar arrays unfurls as Hoffman and Musgrave continue working. Right: Hoffman celebrates the first Hannukah in space, with a spinning dreidel floating nearby.

On the morning of the eighth day, Bowersox used Endeavour’s thrusters to slightly raise and circularize Hubble’s orbit. Hoffman and Musgrave stepped outside for the mission’s fifth and final spacewalk. When the two newly installed solar arrays failed to deploy after ground commanding, they manually deployed them, and the arrays unfurled without incident. They next replaced the solar array drive electronics and fitted an electronic connection box on the GHRS instrument. Hoffman and Musgrave’s final task involved installing covers, manufactured by Bowersox and Nicollier on board the shuttle, on the telescope’s magnetometers. The final spacewalk lasted 7 hours 21 minutes, bringing the mission’s total spacewalk time to 35 hours 28 minutes. Once back inside Endeavour, Hoffman celebrated the first Hanukkah in space during a televised broadcast, displaying a traveling menorah, unlit of course, and a spinning dreidel.

European Space Agency astronaut Claude Nicollier grapples the Hubble Space Telescope, with its high-gain antenna deployed, just prior to release Hubble slowly drifts away from Endeavour A distant view of Hubble, right, with a crescent Moon
Left: European Space Agency astronaut Claude Nicollier grapples the Hubble Space Telescope, with its high-gain antenna deployed, just prior to release. Middle: After its release, Hubble slowly drifts away from Endeavour. Right: A distant view of Hubble, right, with a crescent Moon.

On flight day nine, Nicollier grappled Hubble with the RMS for the final time and lifted it above the payload bay. Ground controllers commanded its aperture door to open, and Nicollier released the telescope. Bowersox fired Endeavour’s thrusters to slowly back away from the telescope. The next day, the astronauts enjoyed a well-deserved day of rest. They returned the shuttle’s cabin pressure to 14.7 psi and tidied up the spacecraft. On the mission’s 11th day, Covey and Bowersox tested Endeavour’s flight control surfaces and practiced touchdowns using a laptop computer, all in preparation for deorbit, entry, and landing the following day.

Astronaut Richard O. Covey guides Endeavour to a landing at NASA’s Kennedy Space Center (KSC) in Florida Workers at KSC continue to safe Endeavour following its landing Images of M100 galactic nucleus before, left, and after the first servicing mission showing the improved optical qualities
Left: Astronaut Richard O. Covey guides Endeavour to a landing at NASA’s Kennedy Space Center (KSC) in Florida. Middle: Workers at KSC continue to safe Endeavour following its landing. Right: Images of M100 galactic nucleus before, left, and after the first servicing mission showing the improved optical qualities.

On Dec. 13, 1993, their 12th and final day in space, the astronauts donned their pressure suits and prepared for the return to Earth. Due to predicted worsening weather conditions at KSC, Mission Control elected to bring them home one orbit earlier than planned. Covey guided Endeavour to a smooth landing at night at KSC, concluding a flight of 10 days, 19 hours, 59 minutes. They circled the Earth 163 times. Within a month, new images from Hubble indicated the repairs returned the telescope to its expected capabilities, providing astronomers with a unique observation platform. The lessons learned from planning and executing the complex series of spacewalks, with extensive coordination with teams on the ground, proved highly useful not only for future Hubble servicing mission but also for the difficult spacewalks required to assemble and maintain the International Space Station.

Timeline of the Hubble Space Telescope’s instruments and their replacements during servicing missions Hubble as it appeared after its release during the final servicing mission in 2009
Left: Timeline of the Hubble Space Telescope’s instruments and their replacements during servicing missions. Right: Hubble as it appeared after its release during the final servicing mission in 2009.

Although the STS-61 crew’s work left the Hubble Space Telescope in better condition than originally designed, over the years it required additional servicing to ensure it met its expected 15-year on-orbit life. Four additional shuttle crews serviced the telescope between 1997 and 2009, and today it carries a suite of instruments far more advanced than its original complement. During the five servicing missions, 16 space walking astronauts conducted 23 spacewalks totaling more than 165 hours, or just under 7 days, to make repairs or improvements to the telescope’s capabilities. To summarize the discoveries made by scientists using data from the Hubble Space Telescope is well beyond the scope of this article. Suffice it to say that during its more than 30 years of operation, information and images returned by Hubble continue to revolutionize astronomy, literally causing scientists to rewrite textbooks, and have dramatically altered how the public views the wonders of the universe. On the technical side, the launch of Hubble and the servicing missions to maintain and upgrade its capabilities have proven conclusively the value of maintainability of space-based scientific platforms. 

Watch the STS-61 crew narrate a video of their Hubble servicing mission.

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Dec 04, 2023

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      The new movie of Chandra (red) and Palomar (blue) data helps break down what is playing out in the Guitar Nebula. X-rays from Chandra show a filament of energetic matter and antimatter particles, about two light-years or 12 trillion miles long, blasting away from the pulsar (seen as the bright white dot connected to the filament).
      Astronomers have nicknamed the structure connected to the pulsar PSR B2224+65 as the “Guitar Nebula” because of its distinct resemblance to the instrument in glowing hydrogen light. The guitar shape comes from bubbles blown by particles ejected from the pulsar through a steady wind. Because the pulsar is moving from the lower right to the upper left, most of the bubbles were created in the past as the pulsar moved through a medium with variations in density.
      X-ray: NASA/CXC/Stanford Univ./M. de Vries et al.; Optical: (Hubble) NASA/ESA/STScI and (Palomar) Hale Telescope/Palomar/CalTech; Image Processing: NASA/CXC/SAO/L. Frattare At the tip of the guitar is the pulsar, a rapidly rotating neutron star left behind after the collapse of a massive star. As it hurtles through space it is pumping out a flame-like filament of particles and X-ray light that astronomers have captured with Chandra.
      How does space produce something so bizarre? The combination of two extremes — fast rotation and high magnetic fields of pulsars — leads to particle acceleration and high-energy radiation that creates matter and antimatter particles, as electron and positron pairs. In this situation, the usual process of converting mass into energy, famously determined by Albert Einstein’s E = mc2 equation, is reversed. Here, energy is being converted into mass to produce the particles.
      Particles spiraling along magnetic field lines around the pulsar create the X-rays that Chandra detects. As the pulsar and its surrounding nebula of energetic particles have flown through space, they have collided with denser regions of gas. This allows the most energetic particles to escape the confines of the Guitar Nebula and fly to the right of the pulsar, creating the filament of X-rays. When those particles escape, they spiral around and flow along magnetic field lines in the interstellar medium, that is, the space in between stars.
      The new movie shows the pulsar and the filament flying towards the upper left of the image through Chandra data taken in 2000, 2006, 2012 and 2021. The movie has the same optical image in each frame, so it does not show changes in parts of the “guitar.” A separate movie obtained with data from NASA’s Hubble Space Telescope (obtained in 1994, 2001, 2006, and 2021) shows the motion of the pulsar and the smaller structures around it.
      To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video
      Hubble Space Telescope data: 1994, 2001, 2006, and 2021.X-ray: NASA/CXC/Stanford Univ./M. de Vries et al.; Optical full field: Palomar Obs./Caltech & inset: NASA/ESA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare) A study of this data has concluded that the variations that drive the formation of bubbles in the hydrogen nebula, which forms the outline of the guitar, also control changes in how many particles escape to the right of the pulsar, causing subtle brightening and fading of the X-ray filament, like a cosmic blow torch shooting from the tip of the guitar.
      The structure of the filament teaches astronomers about how electrons and positrons travel through the interstellar medium. It also provides an example of how this process is injecting electrons and positrons into the interstellar medium.
      A paper describing these results was published in The Astrophysical Journal and is available here.
      NASA’s Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
      Read more from NASA’s Chandra X-ray Observatory.
      Learn more about the Chandra X-ray Observatory and its mission here:
      https://www.nasa.gov/chandra
      https://chandra.si.edu
      Visual Description:
      This release features two short videos and a labeled composite image, all featuring what can be described as a giant flame-throwing guitar floating in space.
      In both the six second multiwavelength Guitar Nebula timelapse video and the composite image, the guitar shape appears at our lower left, with the neck of the instrument pointing toward our upper left. The guitar shape is ghostly and translucent, resembling a wispy cloud on a dark night. At the end of the neck, the guitar’s headstock comes to a sharp point that lands on a bright white dot. This dot is a pulsar, and the guitar shape is a hydrogen nebula. The nebula was formed when particles being ejected by the pulsar produced a cloud of bubbles. The bubbles were then blown into a curvy guitar shape by a steady wind. The guitar shape is undeniable, and is traced by a thin white line in the labeled composite image.
      The pulsar, known as PSR B2224+65, has also released a long filament of energetic matter and antimatter particles approximately 12 trillion miles long. In both the composite image and the six second video, this energetic, X-ray blast shoots from the bright white dot at the tip of the guitar’s headstock, all the way out to our upper righthand corner. In the still image, the blast resembles a streak of red dots, most of which fall in a straight, densely packed line. The six second video features four separate images of the phenomenon, created with Chandra data gathered in 2000, 2006, 2012, and 2021. When shown in sequence, the density of the X-ray blast filament appears to fluctuate.
      A 12 second video is also included in this release. It features four images that focus on the headstock of the guitar shape. These images were captured by the Hubble Space Telescope in 1994, 2001, 2006, and 2021. When played in sequence, the images show the headstock shape expanding. A study of this data has concluded that the variations that drive the formation of bubbles in the hydrogen nebula also control changes in the pulsar’s blast filament. Meaning the same phenomenon that created the cosmic guitar also created the cosmic blowtorch shooting from the headstock.
      View the full article
    • By NASA
      On Nov. 16, 2009, space shuttle Atlantis began its 31st trip into space, on the third Utilization and Logistics Flight (ULF3) mission to the International Space Station, the 31st shuttle flight to the orbiting lab. During the 11-day mission, the six-member STS-129 crew worked with the six-person Expedition 21 crew during seven days of docked operations. The mission’s primary objectives included delivering two external logistics carriers and their spare parts, adding nearly 15 tons of hardware to the station, and returning a long-duration crew member, the last to return on a shuttle. Three of the STS-129 astronauts conducted three spacewalks to transfer spare parts and continue assembly and maintenance of the station. As a group of 12, the joint crews celebrated the largest and most diverse Thanksgiving gathering in space.

      Left: Official photograph of the STS-129 crew of Leland D. Melvin, left, Charles O. Hobaugh, Michael J. Foreman, Robert “Bobby” L. Satcher, Barry “Butch” E. Wilmore, and Randolph “Randy” J. Bresnik. Middle: The STS-129 crew patch. Right: The ULF3 payload patch.
      The six-person STS-129 crew consisted of Commander Charles O. Hobaugh, Pilot Barry “Butch” E. Wilmore, and Mission Specialists Randolph “Randy” J. Bresnik, Michael J. Foreman, Leland D. Melvin, and Robert “Bobby” L. Satcher. Primary objectives of the mission included launch and transfer to the station of the first two EXPRESS Logistics Carriers (ELC-1 and ELC-2) and their multiple spare parts, and the return of NASA astronaut and Expedition 20 and 21 Flight Engineer Nicole P. Stott, the last astronaut to rotate on the shuttle.

      Left: In the Orbiter Processing Facility (OPF) at NASA’s Kennedy Space Center in Florida, workers finish processing Atlantis for STS-129. Right: Space shuttle Atlantis rolls over from the OPF to the Vehicle Assembly Building.

      Left: Atlantis rolls out to Launch Pad 39A. Right: The STS-129 crew during the Terminal Countdown Demonstration Test.
      Atlantis returned to NASA’s Kennedy Space Center (KSC) from its previous mission, STS-125, on June 2, 2009, and workers towed it to the Orbiter Processing Facility (OPF) to prepare it for STS-129. The orbiter rolled over to the Vehicle Assembly Building on Oct. 6, and after mating with its external tank and twin solid rocket boosters, rolled out to Launch Pad 39A on Oct. 14, targeting a Nov. 16 launch. Six days later, the six-member crew participated in the Terminal Countdown Demonstration Test, essentially a dress rehearsal of the actual countdown for launch, returning to Houston for final training. They returned to KSC on Nov. 13 to prepare for launch.

      Left: With Atlantis sitting on Launch Pad 39A, the Ares 1-X rocket lifts off from Launch Pad 39B. Right: The payload canister arrives at Launch Pad 39A.

      Left: The STS-129 astronauts leave crew quarters for the ride to Launch Pad 39A. Right: Liftoff of space shuttle Atlantis on STS-129.
      On Nov. 16, at 2:28 p.m. EST, space shuttle Atlantis lifted off from Launch Pad 39A to begin its 31st trip into space, carrying its six-member crew on the ULF3 space station outfitting and resupply mission. Eight and a half minutes later, Atlantis and its crew had reached orbit. The flight marked Hobaugh’s third time in space, having flown on STS-104 and STS-118, Foreman’s and Melvin’s second, having flown on STS-123 and STS-122, respectively, while Wilmore, Bresnik, and Satcher enjoyed their first taste of weightlessness.

      Left: The two EXPRESS Logistics Carriers in Atlantis’ payload bay. Middle: Leland D. Melvin participates in the inspection of Atlantis’ thermal protection system. Right: The Shuttle Remote Manipulator System grasps the Orbiter Boom Sensor System for the inspection.
      After reaching orbit, the crew opened the payload bay doors, deployed the shuttle’s radiators, and removed their bulky launch and entry suits, stowing them for the remainder of the flight. The astronauts spent six hours on their second day in space conducting a detailed inspection of Atlantis’ nose cap and wing leading edges, with Hobaugh, Wilmore, Melvin, and Bresnik taking turns operating the Shuttle Remote Manipulator System (SRMS), or robotic arm, and the Orbiter Boom Sensor System (OBSS).

      Left: The International Space Station as seen from Atlantis during the rendezvous and docking maneuver. Middle: Atlantis as seen from the space station, showing the two EXPRESS Logistics Carriers (ELC) in the payload bay. Right: View of the space station from Atlantis during the rendezvous pitch maneuver, with the Shuttle Remote Manipulator System grasping ELC-1 in preparation for transfer shortly after docking.
      On the mission’s third day, Hobaugh assisted by his crewmates brought Atlantis in for a docking with the space station. During the rendezvous, Hobaugh stopped the approach at 600 feet and completed the Rendezvous Pitch Maneuver so astronauts aboard the station could photograph Atlantis’ underside to look for any damage to the tiles. Shortly after docking, the crews opened the hatches between the two spacecraft and the six-person station crew welcomed the six-member shuttle crew. After the welcoming ceremony, Stott joined the STS-129 crew, leaving a crew of five aboard the station. Melvin and Bresnik used the SRMS to pick up ELC-1 from the payload bay and hand it off to Wilmore and Expedition 21 NASA astronaut Jeffrey N. Williams operating the Space Station Remote Manipulator System (SSRMS), who then installed it on the P3 truss segment.

      Images from the first spacewalk. Left: Michael J. Foreman unstows the S-band Antenna Support Assembly prior to transferring it to the station. Middle: Robert “Bobby” L. Satcher lubricates the robotic arm’s Latching End Effector. Right: Satcher’s image reflected in a Z1 radiator panel.
      During the mission’s first of three spacewalks on flight day four, Foreman and Satcher ventured outside for six hours and 37 minutes. During the excursion, with robotic help from their fellow crew members, they transferred a spare S-band Antenna Support Assembly from the shuttle’s payload bay to the station’s Z1 truss. Satcher, an orthopedic surgeon by training, performed “surgery” on the station’s main robotic arm as well as the robotic arm on the Kibo Japanese module, by lubricating their latching end effectors. One day after joining Atlantis’ crew, Stott celebrated her 47th birthday.

      Left: Space station crew member Jeffery N. Williams assists STS-129 astronaut Leland D. Melvin in operating the space station’s robotic arm to transfer and install the second EXPRESS Logistics Carrier (ELC2) on the S3 truss. Middle: The station robotic arm installs ELC2 on the S3 truss. Right: Michael J. Foreman, left, and Randolph J. Bresnik during the mission’s second spacewalk.
      On the mission’s fifth day, the astronauts performed another focused inspection of the shuttle’s thermal protection system. The next day, through another coordinated robotic activity involving the shuttle and station arms, the astronauts transferred ELC-2 and its complement of spares from the payload bay to the station’s S3 truss. Foreman and Bresnik completed the mission’s second spacewalk. Working on the Columbus module, they installed the Grappling Adaptor to On-Orbit Railing (GATOR) fixture that includes a system used for ship identification and an antenna for Ham radio operators. They next installed a wireless video transmission system on the station’s truss. This spacewalk lasted six hours and eight minutes.

      Left: Randolph J. Bresnik during the third STS-129 spacewalk. Middle: Robert “Bobby” L. Satcher during the third spacewalk. Right: The MISSE 7 exposure experiment suitcases installed on ELC2.
      Following a crew off duty day, on flight day eight Satcher and Bresnik exited the airlock for the mission’s third and final spacewalk. Their first task involved moving an oxygen tank from the newly installed ELC-2 to the Quest airlock. They accomplished this task with robotic assistance from their fellow crew members. Bresnik retrieved the two-suitcase sized MISSE-7 experiment containers from the shuttle cargo bay and installed them on the MISSE-7 platform on ELC-2, opening them to begin their exposure time. This third spacewalk lasted five hours 42 minutes.

      Left: An early Thanksgiving meal for 12 aboard the space station. Right: After the meal, who has the dishes?
      Thanksgiving Day fell on the day after undocking, so the joint crews celebrated with a meal a few days early. The meal represented not only the largest Thanksgiving celebration in space with 12 participants, but also the most international, with four nations represented – the United States, Russia, Canada, and Belgium (representing the European Space Agency).

      Left: The 12 members of Expedition 21 and STS-129 pose for a final photograph before saying their farewells. Right: The STS-129 crew, now comprising seven members.

      A selection of STS-129 Earth observation images. Left: Maui. Middle: Los Angeles. Right: Houston.
      Despite their busy workload, as with all space crews, the STS-129 astronauts made time to look out the windows and took hundreds of photographs of their home planet.

      Left: The space station seen from Atlantis during the flyaround. Middle: Atlantis as seen from the space station during the flyaround, with a now empty payload bay. Right: Astronaut Nicole P. Stott looks back at the station, her home for three months, from the departing Atlantis.
      On flight day nine, the joint crews held a brief farewell ceremony. European Space Agency astronaut Frank De Winne, the first European to command the space station, handed over command to NASA astronaut Williams. The two crews parted company and closed the hatches between the two spacecraft. The next day, with Wilmore at the controls, Atlantis undocked from the space station, having spent seven days as a single spacecraft. Wilmore completed a flyaround of the station, with the astronauts photographing it to document its condition. A final separation burn sent Atlantis on its way.
      The astronauts used the shuttle’s arm to pick up the OBSS and perform a late inspection of Atlantis’ thermal protection system. On flight day 11, Hobaugh and Wilmore tested the orbiter’s reaction control system thrusters and flight control surfaces in preparation for the next day’s entry and landing. The entire crew busied themselves with stowing all unneeded equipment.

      Left: Atlantis about to touch down at NASA’s Kennedy Space Center in Florida. Middle: Atlantis touches down. Right: Atlantis deploys its drag chute as it continues down the runway.

      Left: Six of the STS-129 astronauts pose with Atlantis on the runway at NASA’s Kennedy Space Center in Florida. Right: The welcome home ceremony for the STS-129 crew at Ellington Field in Houston.
      On Nov. 27, the astronauts closed Atlantis’ payload bay doors, donned their launch and entry suits, and strapped themselves into their seats, a special recumbent one for Stott who had spent the last three months in weightlessness. Hobaugh fired Atlantis’ two Orbital Maneuvering System engines to bring them out of orbit and head for a landing half an orbit later. He guided Atlantis to a smooth touchdown at KSC’s Shuttle Landing Facility.
      The landing capped off a very successful STS-129 mission of 10 days, 19 hours, 16 minutes. The six astronauts orbited the planet 171 times. Stott spent 90 days, 10 hours, 45 minutes in space, completing 1,423 orbits of the Earth. After towing Atlantis to the OPF, engineers began preparing it for its next flight, STS-132 in May 2010. The astronauts returned to Houston for a welcoming ceremony at Ellington Field.
      Enjoy the crew narrate a video about the STS-129 mission.
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