Science

35 Years Ago: STS-32 Returns the Long Duration Exposure Facility

35 Years Ago: STS-32 Returns the Long Duration Exposure Facility

On Jan. 9, 1990, space shuttle Columbia took off on its ninth flight, STS-32, from NASA’s Kennedy Space Center (KSC) in Florida. Its five-person crew of Commander Daniel Brandenstein, Pilot James Wetherbee, and Mission Specialists Bonnie Dunbar, Marsha Ivins, and David Low flew a then record-breaking 11-day mission to deploy the Syncom IV-F5 communications satellite for the U.S. Navy and retrieve the Long-Duration Exposure Facility (LDEF). Astronauts aboard a shuttle mission in 1984 deployed the LDEF and scientists eagerly awaited the return of their 57 experiments to study the effects of nearly six years exposure to the low Earth orbit environment. The crew also conducted several middeck experiments in biotechnology and materials processing and used an echocardiograph to study changes in their hearts. 

In November 1988, NASA announced Brandenstein, Wetherbee, Dunbar, Ivins, and Low as the STS-32 crew for the flight then planned for November 1989. Brandenstein, from the Class of 1978, had flown twice before, as pilot on STS-8 in August-September 1983 and commander of STS-51G in June 1985. Dunbar, selected in 1980, had flown once before on STS-61A in October-November 1985. For Wetherbee, Ivins, and Low, all selected in 1984, STS-32 marked their first spaceflight. During the second day of their planned 10-day mission, the astronauts would deploy the Syncom IV-F5, also known as Leasat-5, communications satellite for the U.S. Navy. The main focus of the flight involved the retrieval of LDEF, deployed by the STS-41C crew in April 1984. The original plan had LDEF, containing 57 science and technology experiments, retrieved by the STS-51D crew in February 1985. Delays in the shuttle program first pushed the retrieval to STS-61I in September 1986, and then the Challenger accident delayed it to STS-32. The facility ended up staying in orbit nearly six years instead of the originally intended 10 months. The crew rounded out the mission by conducting a series of middeck science and medical experiments. 

Columbia returned to KSC on Aug. 21, 1989, following STS-28’s landing at Edwards Air Force Base (AFB) in California, and workers towed it to the Orbiter Processing Facility (OPF) the next day. They made 26 modifications to the orbiter, including the installation of the Remote Manipulator System (RMS), or robotic arm, and a fifth set of liquid hydrogen and liquid oxygen tanks to extend the vehicle’s duration in space. Rollover to the nearby Vehicle Assembly Building took place on Nov. 16, where Columbia joined its External Tank and twin Solid Rocket Boosters (SRB) on refurbished Mobile Launch Platform 3, last used in 1975. Rollout took place on Nov. 28 to Launch Pad 39A, newly refurbished since its previous launch in 1986.  

On Dec. 1, engineers and the astronaut crew completed the Terminal Countdown Demonstration Test, a dress rehearsal for the planned Dec. 18 launch. Based on that date and the mission’s planned 10-day duration, the STS-32 crew would have spent Christmas in space, only the third American crew and the first space shuttle crew to do so. However, unfinished work on Pad 39A delayed the launch into January 1990. Trajectory specialists had estimated that due to orbital decay, LDEF would reenter the Earth’s atmosphere by March 1990, so a timely launch remained crucial for mission success. The countdown began on Jan. 4 for an expected Jan. 8 launch, with the crew arriving at KSC on Jan. 5. 

Cloudy skies scrubbed the first launch attempt on Jan. 8. Liftoff took place the next day at 7:35 a.m. EST from Launch Pad 39A, with LDEF 1,500 miles ahead of Columbia. The powered ride to space took 8.5 minutes, placing Columbia into a 215-by-38-mile orbit. A burn of the two Orbiter Maneuvering System (OMS) engines 40 minutes later changed the orbit to the desired 222-by-180-mile altitude. The crew opened the shuttle’s payload bay doors and deployed its radiators. The major activities for the first day in space involved the checkout of the RMS and the first rendezvous maneuver in preparation for the LDEF grapple three days later. The astronauts also activated four of the middeck experiments. On the mission’s second day, Low deployed the 15,000-pound Syncom satellite, releasing it in a frisbee motion out of the payload bay. The satellite extended its antenna, stabilized itself, and 40 minutes after deployment, fired its engine for the first burn to send it to its geostationary orbit. 

Following the Syncom deploy, the crew turned its attention to the rendezvous with LDEF while also continuing the middeck experiments. On Flight Day 3, they completed three rendezvous burns as they steadily continued their approach to LDEF. Soon after awakening on Flight Day 4, the astronauts spotted LDEF appearing as a bright star. After the first of four rendezvous burns, Columbia’s radar locked onto the satellite. As they continued the approach, with three more burns carried out successfully, Dunbar activated the RMS in preparation for the upcoming grapple. Brandenstein took over manual control of Columbia for the final approach and parked the shuttle close enough to LDEF for Dunbar to reach out with the 50-foot arm and grapple the satellite. Brandenstein reported, “We have LDEF.”  

For the next four hours, with Wetherbee flying the orbiter and Dunbar operating the arm, Ivins performed a comprehensive photo survey of LDEF, documenting the effects of nearly six years of space exposure on the various experiments. The survey completed, Dunbar slowly and carefully lowered LDEF into the payload bay, and five latches secured it in place for the ride back to Earth. With the two major goals of their mission completed, the astronauts settled down for the remainder of their 10-day mission conducting science experiments. 

During the mission, the STS-32 crew conducted several middeck experiments. The Protein Crystal Growth experiment used vapor diffusion to grow 120 crystals of 24 different proteins, for study by scientists following their return to Earth. The Characterization of Neurospora Circadian Rhythm experiment studied whether spaceflight affected the daily cycles of pink bread mold. The Fluid Experiment Apparatus performed materials processing research in the microgravity environment. The astronauts used the American Flight Echocardiograph (AFE) to study changes in their hearts as a result of weightlessness. The crew used the large format IMAX camera to film scenes inside the cabin as well as through the windows, such as the capture of LDEF. 

On Jan. 17, Brandenstein celebrated his 47th birthday, the fifth American astronaut to do so in space. His crew presented him with an inflatable plastic cake including candles while controllers in Mission Control passed on their birthday wishes as did his wife and teenage daughter. On the same day, NASA announced the selection of its 13th group of astronauts. Among them, engineer Ronald Sega, Dunbar’s husband, as well as the first female shuttle pilot, Eileen Collins, and the first Hispanic woman astronaut, Ellen Ochoa. 

On Jan. 19, the astronauts awakened for their planned final day in space. However, due to fog at their landing site, Edwards AFB in California, Mission Control first informed them that they would have to spend an extra orbit in space, and finally decided to delay the landing by an entire day. With their experiments already packed, the crew spent a quiet day, looking at the Earth and using up what film still remained. As they slept that night, they passed the record for the longest space shuttle mission, set by STS-9 in 1983.  

In preparation for reentry, the astronauts donned their orange spacesuits and closed the payload bay doors. A last-minute computer problem delayed reentry by one orbit, then Brandenstein and Wetherbee oriented Columbia into the deorbit attitude, with the OMS engines facing in the direction of travel. Over the Indian Ocean, they fired the two engines for 2 minutes 48 seconds to bring the spacecraft out of orbit. They reoriented the orbiter to fly with its heat shield exposed to the direction of flight as it encountered Earth’s atmosphere at 419,000 feet. The buildup of ionized gases caused by the heat of reentry prevented communications for about 15 minutes but provided the astronauts a great light show. After completing the Heading Alignment Circle turn, Brandenstein aligned Columbia with the runway, and Wetherbee lowered the landing gear. Columbia touched down and rolled to a stop, making the third night landing of the shuttle program and ending a 10-day 21-hour 1-minute flight, the longest shuttle flight up to that time, having completed 172 orbits of the Earth.  

Other records set by the astronauts on this mission included Brandenstein as the new record holder for most time spent in space by a shuttle crew member – 24 days – and Dunbar accumulating the most time in space by a woman – 18 days – up to that time. Following eight hours of postflight medical testing, the astronauts boarded a jet bound for Houston’s Ellington Field, where they reunited with their families and took part in a welcome home ceremony led by Aaron Cohen, director of NASA’s Johnson Space Center. 

Following postlanding inspections, workers placed Columbia, with LDEF still cradled in its payload bay, atop a Shuttle Carrier Aircraft, a modified Boeing-747, and the combination left Edwards on Jan. 25. Following a refueling stop at Monthan Davis AFB in Tucson, an overnight stay at Kelly AFB in San Antonio, and another refueling stop at Eglin AFB in Fort Walton Beach, Florida, Columbia and LDEF arrived back at KSC on Jan. 26. The next day, workers towed Columbia to the OPF and on Jan. 30 lifted LDEF out of its payload bay, in preparation for the detailed study of the effects of nearly six years in space on the 57 experiments it carried. Meanwhile, workers began to prepare Columbia for its next flight, STS-35 in December 1990. 

Enjoy the crew narrate a video of the STS-32 mission. Read Brandenstein‘s and Dunbar‘s recollections of the STS-32 mission in their oral histories with the JSC History Office. For an overview of the LDEF project, enjoy this video. For detailed information on the results of the LDEF experiments, follow this link

Article by:Source John J. Uri

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