STS-80

STS-80 was the eightieth mission of NASA's Space Shuttle program, launched aboard the orbiter Columbia on November 19, 1996, at 2:55 p.m. EST from Launch Pad 39B at Kennedy Space Center, and it marked the final shuttle flight of that year.^[1] The mission, commanded by Kenneth D. Cockrell with pilot Kent V. Rominger and mission specialists Tamara E. Jernigan, Thomas D. Jones, and Story Musgrave, lasted 17 days, 15 hours, 53 minutes, and 18 seconds, completing 279 orbits of Earth before landing on December 7, 1996, at 6:49 a.m. EST on Runway 33 at Kennedy Space Center.^[1]^[2] The primary objectives of STS-80 focused on deploying, operating, and retrieving two free-flying research platforms: the Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer-Shuttle Pallet Satellite II (ORFEUS-SPAS II) for astronomical observations in ultraviolet and extreme ultraviolet wavelengths, and the Wake Shield Facility-3 (WSF-3) for growing high-quality semiconductor thin films in the vacuum of space.^[1]^[2] Additional payloads included the Midcourse Space Experiment (MSX) for missile detection and tracking research, the Shuttle Electromagnetic Experiment (SEM) to study spacecraft charging, and various middeck experiments such as the Commercial Generic Bioprocessing Apparatus (CGBA), the Cell Matrix Immobilized Culture (CMIX-5), and physiological studies like NIH-R4 on protein crystal growth.^[2] The crew successfully used the orbiter's Remote Manipulator System to deploy ORFEUS-SPAS II on flight day 2 and retrieve it on flight day 14, while WSF-3 was deployed on flight day 4 and retrieved on flight day 7, allowing for three days of epitaxial film growth experiments.^[1]^[2] Notable aspects of the mission included the evaluation of the Orbiter Space Vision System (OSVS) for future International Space Station assembly tasks, achieving berthing accuracies within one inch and one degree, and the cancellation of two planned extravehicular activities (EVAs) due to a jammed airlock hatch from a loose screw and related spacesuit cooling concerns, which were investigated through onboard video analysis.^[2] The mission was extended by one day to complete additional ORFEUS-SPAS objectives, and landing was delayed twice due to poor weather, ultimately setting a record for the longest Space Shuttle flight at the time.^[1]^[2] Overall, STS-80 advanced microgravity research in materials science, astrophysics, and biotechnology while testing hardware critical for subsequent shuttle and station operations.^[1]

Mission background

Objectives

The primary objectives of STS-80 centered on the deployment, operation, and retrieval of two free-flying research spacecraft to advance astrophysics and materials science in microgravity. The Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer-Shuttle Pallet Satellite II (ORFEUS-SPAS II) was tasked with conducting astronomical observations in the far-ultraviolet (90-125 nm) and extreme-ultraviolet (40-90 nm) spectra to study hot stellar atmospheres, white dwarfs, supernova remnants, galaxies, and the interstellar medium, using a 1-meter telescope equipped with spectrographs including the International Moderate Resolution Imaging Spectrometer (IMAPS) for high-resolution analysis of interstellar gas.^[3] The mission planned for more than 100 observations of approximately 50 astronomical objects.^[3] Similarly, the Wake Shield Facility-3 (WSF-3), a 12-foot-diameter disk-shaped satellite, sought to create an ultra-vacuum environment in the shuttle's orbital wake to grow high-purity epitaxial thin films for semiconductor applications, such as aluminum gallium arsenide, targeting seven growth cycles.^[3]^[2] Additional primary goals included conducting a suite of middeck experiments to explore microgravity effects on biological and materials processes. These encompassed the National Institutes of Health Rodents 4 (NIH-R4) experiment, which investigated blood pressure regulation using 24 rats (12 flight and 12 ground control) subjected to high- or low-calcium diets; the Commercial Crystal Growth for Space-A (CCM-A), examining microgravity's impact on bone cell gene expression related to transforming growth factor-beta (TGF-β); the Biological Research in Canisters-09 (BRIC-09), studying genetic expression in approximately 200 tomato and tobacco seedlings across 22 petri dishes; the Commercial Materials Dispersion and Integration Science-5 (CMIX-5), performing tests on protein crystal growth, combustion, fluid management, materials science, and biological processes; the Visualization in an Experimental Water-CPL (VIEW-CPL), testing capillary pumped loop technology for spacecraft thermal management through 14 cycles; and the Space Experiment Module (SEM), a student-led initiative with experiments on microgravity effects on bacteria, crystals, and other materials to enhance educational access to space research.^[3]^[2]^[1] Secondary objectives focused on operational and technological evaluations for future missions, including testing the Orbiter Space Vision System (OSVS) to monitor payload positioning and alignment with high precision (within 1 inch and 1 degree) for International Space Station assembly tasks, and assessing extravehicular activity (EVA) tools and procedures through two planned 6-hour spacewalks on flight days 10 and 12.^[3]^[2] Additional payloads included the Midcourse Space Experiment (MSX) for missile detection and tracking research.^[1] The mission was originally planned for 16 days but was extended by one day to complete additional objectives, including ORFEUS-SPAS operations, with landing delayed further due to weather.^[2]

Preparations

The STS-80 mission was assigned to the Space Shuttle Columbia (OV-102) for its 21st flight, with preparations centered at Kennedy Space Center's Launch Complex 39B.^[1] Mission planning emphasized the integration of key payloads, including the ORFEUS-SPAS II (Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer-Shuttle Pallet Satellite II), a reusable free-flying platform approximately 12 feet in diameter equipped with ultraviolet and extreme ultraviolet spectrometers for astrophysics observations, and the Wake Shield Facility-3 (WSF-3), a 12-foot-diameter disk-shaped satellite designed to create an ultra-vacuum environment in its wake for growing high-quality thin films for semiconductor applications.^[2]^[4] Vehicle processing began in July 1996, with Columbia moved to the Orbiter Processing Facility on July 7 for maintenance and payload integration, followed by transfer to the Vehicle Assembly Building on October 9 and rollout to Pad 39B on October 16.^[4] The Solid Rocket Boosters underwent refurbishment, including analysis of nozzle erosion observed on the previous STS-79 flight, which contributed to schedule shifts; External Tank ET-80 was loaded with liquid hydrogen and liquid oxygen propellants as the structural backbone for the stack.^[2]^[5] The payload bay was configured with ORFEUS-SPAS II secured in bays 1-2 forward, WSF-3 in bays 4-5 aft, and middeck lockers accommodating secondary experiments such as the Space Experiment Module and various middeck payloads.^[2]^[6] Preparations encountered multiple delays from the original October 31, 1996, target. Hurricane Fran in early September halted SRB stacking in the Vehicle Assembly Building, prompting a rescheduling to November 8; subsequent issues, including a malfunction in the SRB hydraulic test stand and ongoing nozzle erosion assessments, further postponed the date.^[4]^[1] A Flight Readiness Review on October 28 and a Delta review on November 4 targeted no earlier than November 15, but launch attempts were scrubbed on November 15 due to weather and on November 16 due to high concentrations of hydrogen gas in the aft compartment; the launch occurred on November 19 after a hold to verify hydrogen levels.^[7]^[2] The crew arrived at Kennedy Space Center on November 14, 1996, for final rehearsals, including the Terminal Countdown Demonstration Test.^[2] The countdown initiated on November 19 at 6:55 a.m. EST, culminating in liftoff at 2:55 p.m. EST after a brief hold at T-31 seconds to verify gaseous hydrogen concentrations in the aft compartment.^[2]^[7]

Crew

Members

The STS-80 mission crew comprised five highly experienced astronauts, including Commander Kenneth D. Cockrell, Pilot Kent V. Rominger, and Mission Specialists Tamara E. Jernigan, Story Musgrave, and Thomas D. Jones, whose collective prior spaceflight time exceeded 2,000 hours and diverse expertise in engineering, aviation, astrophysics, medicine, and planetary science supported the mission's microgravity research and satellite operations.^[3] This team brought a total of 13 previous shuttle missions to STS-80, enabling effective payload handling and contingency management during the 17-day flight, which set a then-record for shuttle duration.^[8]^[9]^[10]^[11]^[12] Kenneth D. Cockrell served as mission commander, marking his third spaceflight; a retired U.S. Navy Captain with over 12,100 flying hours, including 650 carrier landings in aircraft such as the A-7 and F/A-18, Cockrell held a B.S. in mechanical engineering from the University of Texas (1972) and an M.S. in aeronautical systems from the University of West Florida (1974).^[8] Selected as an astronaut in 1991, his prior missions included STS-56 in 1993, where he piloted Discovery during atmospheric research, and STS-69 in 1995, commanding Endeavour on a flight testing satellite retrieval techniques, accumulating 482 hours in space before STS-80.^[8] As commander, Cockrell oversaw the deployment and retrieval of the Wake Shield Facility and ORFEUS satellites, leveraging his test pilot background for precise orbital maneuvers.^[8] Kent V. Rominger acted as pilot on his second spaceflight; a U.S. Navy Captain with more than 7,000 hours in over 35 aircraft types and 685 carrier landings, primarily in the F-14 Tomcat, Rominger earned a B.S. in civil engineering from Colorado State University (1978) and an M.S. in aeronautical engineering from the U.S. Naval Postgraduate School (1987).^[9] Joining NASA as an astronaut in 1992, his previous mission was STS-73 in 1995, piloting Columbia during the extended-duration life sciences experiment, logging 15 days, 21 hours, and 52 minutes in space.^[9] Rominger's aviation expertise contributed to vehicle operations and rendezvous activities essential for the mission's satellite handling.^[9] Tamara E. Jernigan, an astrophysicist, flew as a mission specialist on her fourth spaceflight; holding a B.S. in physics and M.S. in engineering science from Stanford University (1981, 1983), an M.S. in astronomy from the University of California, Berkeley (1985), and a Ph.D. in space physics and astronomy from Rice University (1988), she conducted research at NASA Ames before her 1985 astronaut selection.^[10] Her prior missions encompassed STS-40 in 1991 (Spacelab life sciences), STS-52 in 1992 (materials research), and STS-67 in 1995 as payload commander (astronomy observatory), totaling 854 hours in space.^[10] Jernigan's scientific background was pivotal for ORFEUS operations, focusing on extreme ultraviolet spectroscopy to advance astronomical data collection.^[10] Story Musgrave, the mission's most seasoned astronaut at age 61—the oldest to fly on a shuttle mission—served as a mission specialist on his sixth flight; a physician and engineer with an extraordinary educational record including a B.S. in mathematics and statistics from Syracuse University (1958), M.D. from Columbia University (1964), M.S. in physiology and biophysics from the University of Kentucky (1966), and additional degrees in business, chemistry, and literature, he amassed 17,700 flight hours as a Marine Corps and NASA pilot.^[11] Selected in NASA's 1967 astronaut class, Musgrave's prior missions included STS-6 in 1983 (first Challenger flight), STS-51-F in 1985 (Spacelab-2), STS-33 in 1989 (Department of Defense), STS-44 in 1991 (satellite deployment), and STS-61 in 1993 (Hubble Space Telescope repair with three EVAs), accumulating 858 hours.^[11] His multidisciplinary expertise supported contingency planning, extravehicular preparations as the intravehicular crewmember, and Wake Shield Facility operations.^[11] Thomas D. Jones functioned as a mission specialist on his third spaceflight; a planetary scientist with a B.S. in basic sciences from the U.S. Air Force Academy (1977) and a Ph.D. in planetary science from the University of Arizona (1988), he logged over 2,000 hours as a B-52 pilot in the Air Force before transitioning to asteroid research and NASA selection in 1990.^[12] His earlier missions were STS-59 in 1994 (Space Radar Laboratory-1) and STS-68 in 1994 as payload commander (Space Radar Laboratory-2), totaling 539 hours in space.^[12] Jones operated the Wake Shield Facility, applying his physics knowledge to thin-film growth experiments in microgravity.^[12]

Assignments

The STS-80 crew assignments designated specific seating positions and operational roles to optimize mission execution, with Commander Kenneth D. Cockrell in seat 1, Pilot Kent V. Rominger in seat 2, Mission Specialist Story Musgrave in seat 3, Mission Specialist Thomas D. Jones in seat 4, and Mission Specialist Tamara E. Jernigan in seat 5 for launch.^[13] For landing, Musgrave stood during reentry while the others occupied the same seats.^[13] Cockrell, as commander, oversaw overall mission command, navigation, and vehicle operations, including contingency rendezvous procedures for which he served as prime.^[3] Rominger, the pilot, managed spacecraft piloting, ascent and entry phases, and supported remote manipulator system (RMS) operations as backup, while also serving as prime for certain middeck experiments such as the Commercial Materials Dispersion Processing in Space (CMIX) and Visual Interface for Earth Observations with Computational Processor and Link (VIEW-CPL).^[3]^[2] Jernigan, designated as Mission Specialist 1 and extravehicular activity (EVA) crewmember 1, was responsible for ORFEUS-SPAS II deployment and retrieval operations, including RMS support, astronomical data management, and Orbiter Space Vision System evaluations; she also backed up middeck experiments like the Biological Research in Canisters (BRIC).^[3] Musgrave, as Mission Specialist 3 and EVA intravehicular crewmember, led EVA preparations and commanded Wake Shield Facility (WSF-3) free-flyer operations, including deployment and retrieval, while providing backup for ORFEUS-SPAS and supporting middeck tasks such as the PARE/NIH-R4 experiment.^[3] Jones, Mission Specialist 2 and EVA crewmember 2, operated as the primary RMS arm for WSF-3 and ORFEUS-SPAS maneuvers, conducted middeck science experiments including BRIC-09 and the Commercial Generic Bioprocessing Apparatus (CGBA), and served as backup for WSF operations and Earth observations.^[3]^[2] In contingency scenarios, Musgrave and Jones formed the primary EVA crew, with Jernigan as alternate, and all mission specialists received cross-training to handle payload malfunctions, such as airlock issues that ultimately canceled the EVAs.^[3]^[2] The crew's prior flight experiences enhanced their ability to adapt to these roles, with Cockrell on his second command, Rominger on his second pilot assignment, Jernigan on her fourth mission, Musgrave on his sixth, and Jones on his third.^[1]

Launch

Countdown

The final countdown for STS-80 proceeded smoothly on November 19, 1996, from the Kennedy Space Center's Launch Control Center in Firing Room 3, following resumption of the countdown clock from a T-19 hour hold point the previous day. The five-member crew awoke at 9:58 a.m. EST, had breakfast around 10:30 a.m., and donned launch and entry suits before departing crew quarters. Transported via the astronaut transfer van, they arrived at Launch Pad 39B around 11:38 a.m. EST (approximately T-3 hours) and completed ingress into Space Shuttle Columbia by 1:05 p.m. EST, with no issues reported during strapping-in procedures.^[14]^[2] Weather conditions at Kennedy Space Center were clear and favorable, posing no constraints to the launch commit criteria. The countdown advanced without scrubs, building on prior mission preparations that had included multiple delays but ensured vehicle readiness. At T-31 seconds, around 2:52 p.m. EST, a preplanned 2-minute 47-second hold was executed to assess gaseous hydrogen concentrations in the orbiter's aft engine compartment, which briefly exceeded the 300 ppm limit during liquid hydrogen tank prepressurization; routine verification confirmed compliance with contingency procedures, and the hold was lifted without further delay.^[1]^[2] The solid rocket boosters ignited at T-0, propelling Columbia skyward at 2:55:47 p.m. EST and marking the mission's successful liftoff approximately three minutes after the nominal window opening.^[1]^[2]

Ascent

The Space Shuttle Columbia lifted off from Launch Complex 39B at NASA's Kennedy Space Center on November 19, 1996, at 2:55:47 p.m. EST (19:55:47 UTC), initiating the ascent phase of the STS-80 mission. The launch vehicle, consisting of the orbiter, External Tank (ET), and two Solid Rocket Boosters (SRBs), performed nominally from ignition through initial trajectory. The SRBs provided the primary thrust boost, achieving expected performance levels with no deviations in thrust vectoring or structural integrity.^[1]^[2] At T+2:07, the SRBs separated from the ET as planned, after burning through their propellant and contributing the majority of the vehicle's velocity gain during the first stage of ascent. The three Space Shuttle Main Engines (SSMEs) continued firing, powered by the ET's liquid hydrogen and liquid oxygen, propelling the stack toward preliminary orbit insertion. Main Engine Cutoff (MECO) occurred at T+8:31, at which point the ET was jettisoned, having delivered the required propellants without any pressure or flow anomalies. The ET reentered the atmosphere and disintegrated over the Indian Ocean, consistent with predicted impact zones.^[2] Following ET separation, the Orbital Maneuvering System (OMS) engines executed burns to achieve circularization and fine-tune the trajectory. These maneuvers inserted Columbia into an initial low Earth orbit with a mean altitude of 218 miles (351 km) and an inclination of 28.45 degrees relative to the equator. The mission profile called for a total of 279 orbits over approximately 18 days. Throughout the ascent, all vehicle systems, including guidance, navigation, and propulsion, operated nominally, with no in-flight anomalies reported that affected orbital insertion.^[1]^[2]

Orbital phase

Deployments

During the orbital phase of STS-80, the crew successfully deployed and later retrieved two primary free-flying payloads using the Space Shuttle Columbia's Remote Manipulator System (RMS): the Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer-Shuttle Pallet Satellite II (ORFEUS-SPAS II) and the Wake Shield Facility-3 (WSF-3). These operations demonstrated advanced rendezvous and capture techniques essential for satellite servicing in low Earth orbit.^[1]^[2] ORFEUS-SPAS II was unberthed from Columbia's payload bay and deployed on November 20, 1996, with mission specialist Tamara E. Jernigan operating the RMS to release the 3.5-metric-ton satellite. During its 14-day free flight, the payload conducted ultraviolet astronomical observations using instruments such as the Far Ultraviolet Spectrograph and Extreme Ultraviolet Spectrometer, targeting celestial objects like white dwarfs and the interstellar medium. The satellite completed 239 orbits before Columbia performed a series of rendezvous burns, including non-propulsive coast and mid-course corrections, to close the distance for retrieval on December 3, 1996, via RMS grapple and berthing.^[2]^[1]^[15] WSF-3, a 3.8-meter-diameter disk-shaped satellite, was deployed on November 22, 1996, also using the RMS, initiating a planned mission focused on materials science. Orbiting ahead of Columbia, the facility created an ultra-high vacuum environment of approximately $10^{-14} Torr in its wake shield, allowing for the growth of four thin-film semiconductor samples via molecular beam epitaxy without atmospheric contamination. Retrieval maneuvers began on November 26, 1996, after mission specialists Story Musgrave and Thomas D. Jones attempted a manual capture approach; the effort transitioned to a successful RMS grapple by Jones, followed by berthing in the payload bay. Columbia's rendezvous burns, including height-adjust and non-impulsive corrections, facilitated the operation, with WSF-3's total free-flight time amounting to 4 days and encompassing about 64 orbits.^[2]^[1]^[4]

Experiments

During the STS-80 mission, the crew conducted a series of middeck experiments in the Space Shuttle Columbia's payload bay lockers, focusing on microgravity effects in life sciences, materials processing, fluid physics, and technology development. These experiments operated continuously over the mission's duration of 17 days, 15 hours, and 53 minutes, with the crew performing activations, monitoring, and maintenance to ensure nominal performance. Data and video were downlinked in real-time via the shuttle's Ku-band communications system for ground analysis. All middeck experiments achieved full operational success, with no anomalies reported. Additionally, the Midcourse Space Experiment (MSX) satellite, mounted in the payload bay, conducted autonomous observations for missile detection and tracking research throughout the mission.^[2]^[3] The Space Experiment Module (SEM) investigated plasma wave propagation and other microgravity phenomena using student-designed payloads housed in a 5-cubic-foot Getaway Special canister on the middeck. Activated early in the mission, it ran unattended but with periodic crew checks to verify environmental conditions, providing data on wave interactions in space plasmas.^[3]^[2] NIH-R4, a National Institutes of Health-sponsored rodent experiment, examined the role of dietary calcium in regulating blood pressure and cardiovascular function under microgravity. Thirty-two rats were divided into groups receiving high- or low-calcium diets within middeck lockers; the crew managed feeding, waste collection, and health observations throughout the flight, noting excellent animal condition post-mission.^[3]^[2] NASA/CCM-A (Cell Culture Module-A), formerly known as STL/NIH-C6, studied microgravity's impact on bone cell development by culturing human osteoblast-like cells to assess TGF-β gene expression. The experiment maintained precise temperatures between 35-39°C across 17 measurements in a middeck incubator; crew members handled setup, medium exchanges, and fixation procedures without issues.^[3]^[2] BRIC-09 (Biological Research in Canister-09) explored genetic expression and hormone influences on plant growth in microgravity using 200 tomato and tobacco seeds distributed across 22 petri dishes in five BRIC-60 canisters. The unattended setup on the middeck was activated and deactivated by the crew, yielding nominal growth data for postflight analysis.^[3]^[2] CMIX-5 (Commercial Materials Dispersion Apparatus ITA Experiment-5) produced zeolite crystals and other materials for applications in diabetes treatment, tissue engineering, pest control, and breast cancer research, encompassing over 900 individual tests in bioprocessing modules. Crew operations included initiating dispersion sequences and monitoring crystal formation in the middeck apparatus, resulting in successful sample returns.^[3]^[2] VIEW-CPL (Visualization in an Experimental Water Capillary Pumped Loop) demonstrated thermal management technology for future spacecraft by observing fluid dynamics in a capillary loop evaporator. The crew completed all 14 planned tests on the middeck, capturing video of boiling and flow behaviors under varying heat loads, with data downlinked for immediate review.^[3]^[2] The Space Vision System tested laser-based tracking and vision aids for International Space Station assembly, using the shuttle's Remote Manipulator System for mockup maneuvers. Mission Specialists Tamara Jernigan (prime) and Thomas D. Jones (backup) powered up the system on flight days 2, 11, and 13, recording video from the aft flight deck; operations achieved berthing accuracies within 0.6 inches and 1 degree, supporting real-time ground control.^[3]^[2] Mission Specialist Thomas D. Jones served as the primary operator for most middeck experiments, coordinating crew shifts for around-the-clock monitoring and ensuring seamless integration with the overall payload schedule. In parallel, the crew briefly supported the free-flying ORFEUS-SPAS and Wake Shield Facility experiments through orbital adjustments and data coordination.^[2]^[1]

Extravehicular activity

Planned operations

The STS-80 mission planned two six-hour extravehicular activities (EVAs) as part of the EVA Development Flight Test-05 (EDFT-05) series, aimed at evaluating tools, procedures, and hardware for the assembly and maintenance of the International Space Station (ISS).^[6] These EVAs were designated to occur on Flight Day 10 (November 28, 1996, starting at 9:07 p.m. EST) and Flight Day 12 (November 30, 1996, starting at 9:37 p.m. EST), each lasting approximately 6.5 hours.^[6] Mission Specialist Tamara E. Jernigan served as EV-1 (lead spacewalker, wearing the suit with red stripes), Mission Specialist Thomas D. Jones as EV-2, and veteran Mission Specialist F. Story Musgrave as the intravehicular (IV) crewmember, providing support from inside the orbiter; Pilot Kent V. Rominger assisted by operating the Remote Manipulator System (RMS) arm.^[6] For EVA-1, the primary objectives focused on an end-to-end simulation of a battery orbital replacement unit (ORU) maintenance task, expected to take about three hours, along with evaluations of a small ORU handling tool known as the cable caddy.^[6] EVA-2 emphasized testing operations with a simulated battery ORU from a portable work platform, with roughly two hours allocated per major task, including assessments of worksite stability and tool usability.^[6] These activities were designed to verify Phase 1 ISS hardware integration and procedures, such as ORU exchanges and mobile worksite configurations, to reduce risks in future station construction.^[6] Key equipment included two Extravehicular Mobility Units (EMUs) for the spacewalkers, providing life support and mobility; the RMS for positioning crew and hardware; a 156-pound crane (6 feet tall with a 4- to 17.5-foot extendable boom, capable of handling up to 600 pounds); a simulated battery ORU (approximately 354 pounds, 41 by 39 by 19 inches); the 50-pound cable caddy for small ORU transport; and a portable work platform equipped with an articulating foot restraint and body restraint tether (BRT) for stabilizing the EV-1 during tasks.^[6] Additional tools encompassed a multi-use tether (MUT) for securing ORUs, tools, and handrails, along with torque-multiplication devices and other hand tools for the simulated battery installation and removal.^[6] Procedures began with crew transfer to the airlock, followed by cabin repressurization to 10.4 psi and airlock depressurization to vacuum, enabling egress through the outer hatch via the airlock adapter.^[2] For EVA-1, Jernigan and Jones would install the crane in the payload bay, maneuver the battery ORU using the RMS and MUT, and perform the cable caddy evaluation while translating along orbiter structure using foot restraints and handholds.^[6] In EVA-2, the portable work platform would be attached to the RMS end effector, allowing Jones to ride it for battery operations while Jernigan provided untethered support, testing contingency scenarios like free-flyer capture and ISS assembly demonstrations with the BRT and MUT.^[6] All tasks integrated RMS operations for crew restraint and hardware positioning, with Musgrave monitoring from the aft flight deck.^[6]

Cancellations

During preparations for the first extravehicular activity (EVA) on STS-80, the crew encountered a critical malfunction with the orbiter's airlock hatch on November 29, 1996.^[16] The outer hatch failed to open, preventing pressure equalization between the airlock and the vacuum of space, which was essential for the planned EVA involving astronauts Tamara E. Jernigan and Thomas D. Jones.^[16] This issue arose despite successful pre-EVA pressurization and suit checks, halting the procedure after the crew entered the airlock and attempted to operate the hatch mechanism.^[16] The crew was unable to open the outer hatch after entering the airlock and attempting to operate the mechanism, indicating a problem with the rotary actuator. Troubleshooting in orbit did not reveal the specific cause, and no immediate repair was possible due to the lack of specialized tools and access to the external components.^[16] Post-mission inspection identified the root cause as a loose number 10 screw from the actuator's clutch assembly that had migrated into the gearbox, lodging between a planetary gear and the ring gear and binding the system.^[16] The screw's movement was attributed to the use of non-locking thread inserts instead of the required locking type, allowing it to back out during launch vibrations or orbital operations.^[16] Engineers on the ground debated potential causes like misalignment but confirmed the internal screw jam through disassembly after landing.^[16] The malfunction led to the cancellation of both planned EVAs, which were secondary objectives focused on evaluating EVA tools and procedures, to avoid any risk of damaging the hatch seals or mechanism that could compromise crew safety.^[16] The crew conducted extensive troubleshooting in the airlock for over two hours, with multiple members attempting to manipulate the handle, and later performed internal simulations of EVA tasks to maintain readiness.^[16] No risks to orbital operations or reentry were posed by the issue, as the airlock remained functional for internal use.^[16] Following the mission, all orbiter airlock hatch actuators were removed for recertification, and the design was updated with locking thread inserts and revised torque specifications to prevent recurrence.^[16] This incident underscored the importance of manufacturing precision in critical mechanisms and prompted fleet-wide inspections.^[16]

Reentry and landing

Deorbit

The crew of STS-80 began deorbit preparations on December 6, 1996, by reconfiguring the payload bay to secure experiments and equipment for reentry. This included stowing the Wake Shield Facility and ORFEUS-SPAS II satellite components after their retrieval earlier in the mission. However, unfavorable weather conditions at Kennedy Space Center and Edwards Air Force Base, including low clouds and high winds, postponed the planned landing from December 5, leading to an extension of orbital operations. The payload bay doors were initially closed at 4:14 p.m. EST on December 6 but were reopened approximately three hours later to accommodate the delay and potential further observations; they were securely latched again at 3:09 a.m. EST on December 7 in final preparation for descent.^[2] The deorbit burn commenced with the ignition of the Orbital Maneuvering System (OMS) engines at 5:43 a.m. EST on December 7, 1996, during orbit 278. The dual-engine burn lasted 188 seconds, imparting a velocity change of 316 feet per second (approximately 215 miles per hour) to decelerate the orbiter Columbia from its orbital path. This maneuver, conducted over the Indian Ocean, precisely targeted the reentry corridor while minimizing fuel expenditure and ensuring structural loads remained within safe limits. Post-burn systems checks confirmed nominal performance, with no anomalies reported in propulsion or attitude control.^[2] Following the burn, Columbia's ground track traced westward across the Indian Ocean, southern Africa, and the Atlantic Ocean, aligning with the standard east-coast landing profile. Reentry interface, defined as the point of initial atmospheric contact at 400,000 feet altitude, occurred at approximately 6:05 a.m. EST. As the orbiter descended, aerodynamic heating intensified, with the thermal protection system tiles on the underside reaching peak temperatures of around 3,000 degrees Fahrenheit to dissipate the frictional energy from atmospheric compression. This phase marked the transition from orbital flight to controlled glide, with the vehicle maintaining stability through its reaction control system until blackout.^[2]^[3]

Touchdown

Columbia touched down on Runway 33 at Kennedy Space Center in Florida on December 7, 1996, at 6:49:05 a.m. EST, completing the STS-80 mission after two days of weather-related delays to landing attempts.^[1] The final approach utilized standard dual TACAN guidance for alignment, with the speedbrake deployed to manage descent velocity during the atmospheric phase.^[2] Weather conditions had improved sufficiently for the landing, featuring a light crosswind of 8 knots that remained within operational limits.^[17] The main landing gears made initial contact first at a speed of 203.4 knots equivalent airspeed (KEAS) and a sink rate of 1.0 foot per second (ft/sec), followed by nose gear touchdown 9.7 seconds later at 149.3 KEAS.^[2] The drag chute deployed shortly after main gear contact and was jettisoned after rollout began, resulting in a total rollout distance of 8,721 feet over 62 seconds, with wheels stopping at approximately 7:00 a.m. EST.^[1] No significant anomalies occurred during the touchdown or rollout phases.^[2] Following wheels stop, the crew egressed the orbiter using the shuttle crew transport vehicle and underwent standard post-flight medical evaluations.^[1] The mission concluded with a total duration of 17 days, 15 hours, 53 minutes, and 18 seconds, having completed 279 orbits of Earth.^[1]

Outcomes

Scientific results

The STS-80 mission achieved 100% success in meeting its scientific objectives for all payloads, excluding the canceled extravehicular activities.^[2] The experiments generated a substantial volume of data that surpassed initial expectations, contributing significantly to space-based research archives from the 1990s and enabling subsequent analyses in astrophysics, materials science, and biological sciences.^[2] The ORFEUS-SPAS II free-flyer, focused on far-ultraviolet and extreme-ultraviolet spectroscopy, recorded 422 high-resolution spectra of approximately 150 astronomical objects, including white dwarfs, quasars, and interacting binaries.^[2] With an observing efficiency of 62.5%—exceeding projections due to an extended mission duration—these observations provided higher-quality data than the 1993 predecessor flight, supporting models of stellar evolution and interstellar medium properties.^[2] Post-mission analyses, published in astrophysics journals starting in 1997, utilized this dataset to study phenomena such as high-excitation emission lines and binary system dynamics. The Wake Shield Facility-3 (WSF-3) successfully grew seven epitaxial thin films in its ultra-vacuum wake environment, including gallium arsenide and aluminum gallium arsenide layers, meeting all science goals during a 73-hour free-flight.^[2] These films exhibited superior purity and quality compared to ground-based counterparts, advancing semiconductor applications in electronics and optoelectronics.^[6] Middeck experiments yielded foundational data on microgravity effects across biological and physical domains. The Space Experiment Module (SEM) operated nominally, collecting measurements on plasma interactions and space environment effects for educational and scientific analysis.^[2] NIH-R4 investigated microgravity's impact on rodent physiology, including calcium metabolism and vascular function, with all 14 subjects returning in excellent condition.^[2] The Cell Culture Module-A (CCM-A) operated nominally for bone and muscle cell studies, with cooling system temperatures maintained at 35-39°F across 17 measurements and culture conditions at standard 37°C.^[2] BRIC-09 examined genetic expression in tomato and tobacco seedlings under microgravity, while CMIX-5 advanced research on diabetes, osteoporosis, and cataracts through over 900 cell and tissue samples.^[2] These efforts collectively enhanced understanding of microgravity's biological influences, informing future human spaceflight health strategies.^[2]

Legacy

STS-80 established a benchmark for extended-duration Space Shuttle operations, achieving a mission length of 17 days, 15 hours, 53 minutes, and 18 seconds, which marked the longest single flight in the program's history and demonstrated the vehicle's capability to support prolonged human presence in orbit, paving the way for International Space Station assembly and operations in the late 1990s.^[1]^[18] This duration underscored the reliability of life support systems and crew performance over nearly 18 days, providing critical validation for future long-term missions requiring sustained microgravity exposure.^[19] The mission's canceled extravehicular activities due to a jammed airlock hatch—caused by a screw lodging in the actuator—prompted immediate engineering reviews and led to the rework and recertification of all hatch actuators across the Shuttle fleet, ensuring no recurrences and enhancing safety for subsequent flights, including the Hubble Space Telescope servicing mission STS-82 in February 1997.^[20] Additionally, the successful deployment and retrieval of the free-flying Wake Shield Facility (WSF-3) and Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer-Shuttle Pallet Satellite (ORFEUS-SPAS II) refined techniques for satellite capture using the Remote Manipulator System, directly informing procedures for Hubble servicing missions.^[1]^[19] Key contributions from STS-80 advanced materials science through WSF-3's growth of seven high-quality epitaxial thin films in an ultra-vacuum environment, yielding semiconductors with potential applications in microelectronics and influencing subsequent satellite technology development.^[2] ORFEUS-SPAS II's 422 ultraviolet observations of nearly 150 celestial objects, including stellar atmospheres and supernova remnants, enriched datasets later cross-referenced in analyses from the Hubble Space Telescope and Chandra X-ray Observatory, deepening understanding of cosmic phenomena.^[1]^[21] The mission also gathered human factors data on crew physiology and psychology during extended flight, contributing to NASA's knowledge base for mitigating isolation and microgravity effects in longer-duration explorations.^[19] Following landing, retrieved payloads such as WSF-3 and ORFEUS-SPAS II underwent detailed ground analysis to evaluate experiment outcomes and inform future iterations, while the crew participated in debriefings to document operational insights.^[19] Commander Kenneth D. Cockrell and others continued NASA assignments, but mission specialist F. Story Musgrave retired from the agency in 1997 after this, his sixth and final flight.^[22]^[23] NASA published the official STS-80 Mission Report in early 1997, consolidating technical and scientific findings for program archives.^[19]^[24]