A decade and a half ago, yesterday, on 20 February 2001, the crew of Atlantis glided a textbook landing at Edwards Air Force Base, Calif., wrapping up a 5.3-million-mile (8.5-million-km) mission to install the U.S. Destiny laboratory onto the International Space Station (ISS). As outlined in yesterday’s AmericaSpace history article, the STS-98 crew—Commander Ken Cockrell, Pilot Mark Polansky, and Mission Specialists Bob Curbeam, Marsha Ivins, and Tom Jones—had been training together for more than two years to deliver the 28-foot-long (8.5-meter) cylindrical module onto the station, where it remains to this day, providing a central scientific research hub for the United States’ Earth-orbiting National Laboratory, as well as the heart and brain of the ISS.
After a smooth docking at the station, and becoming only the second shuttle to arrive at the Earth-facing (or “nadir”) interface of the Unity node, via Pressurized Mating Adapter (PMA)-3, Atlantis and her five astronauts were briefly welcomed by the station’s incumbent Expedition 1 crew—Commander Bill Shepherd of NASA and Russian cosmonauts Yuri Gidzenko and Sergei Krikalev—before the hatches were closed, in readiness for the first of three challenging EVAs by Jones and Curbeam. Early on 10 February 2001, Marsha Ivins used the shuttle’s Canadian-built Remote Manipulator System (RMS) mechanical arm to remove the PMA-2 docking adapter from the forward “end” of Unity, in order to make room for the installation of the Destiny lab. Assisted by visual cues from Jones, Ivins “temp-stowed” PMA-2 onto the station’s nascent truss. It marked the start of a joint EVA/robotics operation which would characterize the rest of the mission.
As Jones assisted Ivins, his fellow spacewalker Curbeam removed protective launch covers and disconnected electrical power and cooling umbilicals between Destiny and the shuttle. At 12:23 p.m. EST, Ivins grappled Destiny with the RMS and raised it from the payload bay, “flipping” it 180 degrees and aligning it for a smooth attachment to the Unity forward port at 1:57 p.m., where it was bolted into its permanent home. In a stroke, the work increased the space station’s habitable volume by about 3,800 cubic feet (107.6 cubic meters) to a total of more than 13,000 cubic feet (368 cubic meters) and enhanced the living quarters of Shepherd’s crew by 41 percent. With the 32,000-pound (14,500-kg) lab in place, Jones and Curbeam set to work connecting electrical, power, and data cables. Their work ran smoothly, with the exception of a small ammonia leakage as Curbeam was installing a cooling umbilical. This prompted flight controllers to impose a decontamination procedure, in which Curbeam remained in direct sunlight for 30 minutes and Jones brushed down his suit and equipment. When the duo returned to Atlantis’ airlock, they performed a partial repressurization, in order to flush out any flakes of ammonia, before commencing a final repressurization and subsequent ingress into the orbiter.
Due to the extended decontamination effort, EVA-1 lasted more than 7.5 hours, some 60 minutes longer than intended, but had positioned the STS-98 and Expedition 1 crews favorably to begin activating Destiny’s systems. Later that day, Cockrell and Shepherd began remotely powering up the lab, via laptop computers, with ground controllers continuing this effort through the night. Next morning, at 9:38 a.m. EST, the two commanders opened the hatches and entered Destiny for the first time. Thus began a busy schedule to activate air conditioners, fire extinguishers, computers, internal communications systems, electrical outlets, ventilators, alarms, and air-purification equipment. In order to save weight, the lab was launched with only five of its eventual 24 payload racks in place, and it was a relatively spacious, though spartan, module in which the astronauts and cosmonauts worked. Additional racks were expected to be ferried into orbit aboard subsequent missions, with the Human Research Facility (HRF) having already been loaded into the Multi-Purpose Logistics Module (MPLM) for delivery aboard Shuttle Discovery on STS-102 in March.
Jones and Curbeam’s second EVA got underway at 10:40 a.m. EST on 12 February and saw them again functioning in tandem with RMS operator Ivins. The spacewalkers provided visual assistance as Ivins detached PMA-2 from its temporary perch on the station’s truss and maneuvered it to its new position at the forward end of Destiny, where it would provide the primary docking interface for shuttle visitors, until the arrival of Node-2. With this significant task completed, Jones and Curbeam installed insulating covers over Destiny’s launch restraint pins, installed air vents, wires, handrails, and sockets, and were able to press ahead into several tasks originally planned for EVA-3: connecting computer and electrical cables between PMA-2 and the lab, removing covers from Destiny’s high-quality window, and attaching an external shutter.
After almost seven hours outside the ISS, the astronauts returned inside Atlantis, as flight controllers began commanding the four Control Moment Gyroscopes (CMGs) on the Z-1 truss. Installed the previous year as a means of managing the station’s orientation, they were to be directly controlled through electronics inside Destiny itself. “For command and control, right now, we’re in sort of a crude mode, where we use thruster control to maintain attitude on the space station, and that’s a very propellant-intensive activity,” explained Jones before the flight. “We want to get the gyros … to control the station’s attitude and the software and commanding … that make that possible, are all in the lab. That enables a more fuel-efficient mode of operation, which permits maintaining attitude control with momentum wheels. The Control Moment Gyros are much less disturbing to a microgravity environment than thruster firings are, so that makes a good-quality research environment available on the station.”
This important work was accompanied by “command authority” testing, throughout the week, as the lab’s newly-activated computers were verified as being capable of taking over orientation control from the Russian Orbital Segment (ROS). “The gyros were operating perfectly,” NASA reported on 13 February, “displaying good speeds and normal temperatures as they worked to gently steer the station to provide correct alignment of the U.S. and Russian module solar arrays to the Sun.”
Significantly, Jones and Curbeam’s third and final EVA on 14 February was initially touted by NASA as the 100th spacewalk in U.S. history—blazing a trail which had begun almost 36 years earlier, in the pioneering excursion of Ed White—and the astronauts were tasked with installing a spare S-band communications antenna onto the Z-1 truss, photographing the newly-arrived P-6 photovoltaic arrays, and performing practice efforts for future rescue techniques. “Beamer and I planned to say a few words to honor those spacewalking pioneers before us,” Jones reflected in his memoir, Sky Walking, but this was arrested by a call from Mission Control. Apparently, a recount had been done and concluded that the real 100th U.S. EVA had occurred during their second spacewalk on the 12th. Presenting the note through the aft flight deck window to the astronauts, Polansky told Jones and Curbeam that the message had been conveyed privately, “so we didn’t have egg on our face if somebody checks the numbers.”
NASA’s official news release noted that the astronauts “completed their third and final planned spacewalk,” after almost 5.5 hours, before “pausing to celebrate the mission, which included the 100th spacewalk in United States space history.” Jones and Curbeam displayed a placard to commemorate those EVAs, which occurred from Gemini and Apollo spacecraft, as well as from the shuttle and the Skylab space station, and upon the surface of the Moon. “This achievement, this golden anniversary, so to speak, is a tribute to all the people who have done spacewalks,” Curbeam said. “And we salute all of you and appreciate your hard work and thank you so much.”
However, the 100th-EVA mystery was “one last curveball” to be thrown at the crew, Jones recalled, but although he alluded nothing of significance to the event, it has been pointed out over the years that the apparent “miscount” could reflect an EVA which was performed, but never formally acknowledged. One such candidate was the classified STS-27 mission in December 1988, during which the crew rendezvoused with their just-deployed spy-satellite payload and conducted repairs. Whether these “repairs” included a spacewalk has never been divulged, but it has been offered as one possible explanation.
With Destiny having been installed and activated, the STS-98 crew undocked from the space station and returned safely to Earth on 20 February 2001. Yet their contribution, aside from when the 100th U.S. EVA actually took place, is enormously significant, for the expansion of the ISS very much hinged on the success of their mission. “I try not to dwell too much on the specific significance for our flight, because it’s going to be overshadowed by the significance of the next flight,” said Cockrell in his pre-launch interview. “And they’re all important and each flight is critical to the next flight.” His primary concern was having accomplished all of his assigned tasks, to leave the station ready for the work of the STS-102 crew, commanded by Jim Wetherbee, who were scheduled to arrive in March. That said, Cockrell was keenly aware that getting Destiny activated was necessary in order for the Mission Control Center (MCC) at the Johnson Space Center (JSC) in Houston, Texas, to assume primary command and control of the ISS from Russia.
The lab’s role over the years has seen it provide support for hundreds of experiments in life and microgravity sciences and applications, as well as serving as the central hub for commanding ISS robotic assets and enabling the installation of station hardware and the rendezvous and berthing of visiting vehicles. In September 2002, the role of “science officer” was created in response to the increased emphasis upon research which Destiny’s arrival had enabled and the 2005 NASA Authorization Act designated the unique facility as a “U.S. National Laboratory.” Under the language of the Act, NASA was directed to “increase the utilization of the ISS by other Federal entities and the private sector,” in the advancement of science, technology, engineering, and mathematics. More recently, in September 2011, NASA finalized a co-operative agreement with the independent, non-profit Center for the Advancement of Science in Space (CASIS) to manage the Laboratory.
This is part of a series of history articles, which will appear each weekend, barring any major news stories. Next week’s article will focus on the 50th anniversary of the loss of the original Gemini IX crew in February 1966 and the effect of the tragedy on their lost mission.