Fwd: 18 Years Since STS-77

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From: "Gary Johnson" <gjohnson144@comcast.net>
Date: May 28, 2014 11:26:01 AM CDT
To: "Gary Johnson" <gjohnson144@comcast.net>
Subject: FW: 18 Years Since STS-77

 

 

AmericaSpace

For a nation that explores
May 24th, 2014

Mission for Science and Technology: 18 Years Since STS-77 (Part 1)

By Ben Evans

 

At the cusp of daybreak on 19 May 1996, Endeavour thunders into orbit to begin the multi-faceted STS-77 mission. Photo Credit: NASA

Early on 20 May 1996, astronaut Mario Runco Jr. grappled SPARTAN-207—a small, free-flying spacecraft, equipped with a very unique payload—and unberthed it from Endeavour's payload bay with the shuttle's Canadian-built Remote Manipulator System (RMS) mechanical arm. With his five crewmates, he had launched into orbit barely 24 hours earlier, to kick off the 10-day STS-77 mission. SPARTAN, an acronym for "Shuttle Pointed Autonomous Research Tool for Astronomy," was a frequent flyer aboard the shuttle, having supported numerous astronomical and solar physics experiments, as well as space technology investigations. On STS-77, however, it undertook its most ambitious mission to date. Runco released the satellite, precisely on time at 7:29 a.m. EDT, after which STS-77 Commander John Casper maneuvered the shuttle to a distance of about 820 feet (250 meters). He held the position of his ship for about an hour, then conducted a partial fly-around, to a point directly "above" the satellite, and began an 80-minute-long station-keeping exercise to observe a remarkable experiment—an experiment which carried potentially enormous benefits for a multitude of applications, from space radar to mobile communications, from astronomy to Earth observations, and from environmental research to analyses of soil moisture and ocean salinity. Eighteen years ago this week, STS-77 put the shuttle's many capabilities to work and served as a pathfinder for future International Space Station (ISS) research.

Two hours after Runco released SPARTAN-207, the Inflatable Antenna Experiment (IAE) got underway. Designed and built by L'Garde, Inc., a small aerospace company, based in Tustin, Calif., together with NASA's Jet Propulsion Laboratory of Pasadena, Calif., it sought to inflate a 46-foot-wide (14-meter) Mylar antenna dish, at the apex of three deployable struts, as part of an investigation into how large, expandable structures behaved and functioned in the microgravity environment. Since 1971, L'Garde had pioneered the construction of thin-skinned, multi-task balloons and its products included a decoy missile for the Department of Defense. It had long been recognized that the mass and stowed volume of inflatable space components was significantly less than an equivalent solid structure and that this carried the potential to reduce by 10-100 times the cost of future missions. In 1988, L'Garde began working on the IAE, and, according to the company's founder and vice president, Alan Hirasuna, the $14 million cost of this inflatable antenna was a mere fraction of the $200 million to build a similar-sized antenna with more conventional materials. Moreover, its compactness and 130-pound (60-kg) weight meant that it could be carried aboard much smaller launch vehicles.

At 9:38 a.m. EDT, as six pairs of astronaut eyes and a battery of still, video, and motion-picture camera equipment aboard Endeavour looked on, SPARTAN-207 commanded the deployment of IAE's supporting tripod, each of whose neoprene-coated Kevlar limbs unfolded to a length of 92 feet (28 meters). At their apex, a canister of pressurised nitrogen gas inflated the antenna, in just five minutes, to its full 46 feet (14 meters) diameter. With a silver reflective surface on its topside and a clear underside, the IAE was then observed and photographed over the following 90 minutes by the STS-77 crew and illuminated by an array of lights aboard SPARTAN-207 to precisely measure its smoothness. The antenna was then jettisoned, steadily moving "below" and "ahead" of the satellite, as Casper executed a Reaction Control System (RCS) thruster firing to maneuver Endeavour "above" and "behind" it. They would maintain a distance of 55-70 miles (90-110 km) from SPARTAN-207 for the next two days.

The Inflatable Antenna Experiment (IAE) commences its deployment from the SPARTAN-207 satellite. Photo Credit: NASA

It was a great success for the entire crew, and not least for Casper and Runco, who were making their second shuttle mission together. John Howard Casper, an Air Force colonel, was making his fourth flight overall. He was born in Greenville, S.C., on 9 July 1943 and after high school entered the Air Force Academy to study engineering science. He earned his degree in 1966 and completed a master's qualification in astronautics from Purdue University, early the following year. Following initial flight instruction, Casper received his wings at Reese Air Force Base in Texas, trained on the F-100 Super Sabre, and was despatched to Vietnam, where he flew more than 200 combat missions. Upon his return to the United States, he continued to fly the F-100, as well as the F-4 Phantom, and was assigned as an exchange pilot to a tactical fighter wing at RAF Lakenheath base in England. Casper then attended test pilot school at Edwards Air Force Base, graduated in 1974, and headed the F-4 Test Team, performing weapons separation and avionics testing. He later worked at the Pentagon as deputy chief of the Special Projects Office, developing Air Force positions on requirements, operational concepts, policy, and force structure for tactical and strategic programmes. In February 1990, Casper flew his first mission as pilot of STS-36 and subsequently commanded STS-54 and STS-62.

Mario Runco Jr.'s quite remarkable career path had seen duty as a police state trooper, then a Navy oceanographer and meteorologist and ultimately an astronaut. Born in the Bronx, N.Y., on 26 January 1952, of Italian-American parentage, Runco's close resemblance to Mr. Spock (Leonard Nimoy's character in Star Trek) proved the root of many jokes whilst at NASA. He studied Earth and planetary sciences at the City College of New York and, whilst there, played intercollegiate ice hockey. After graduation in 1974, he moved to Rutgers University for his master's degree in atmospheric physics, again played ice hockey, and spent two years as a research hydrologist, carrying out groundwater surveys for the U.S. Geological Survey on Long Island. In 1977, Runco joined the New Jersey State Police and spent a year as a patrol trooper, then entered the Navy in June of the following year. His early military duties, not surprisingly, took full advantage of his academic and work training: He served as a research meteorologist at the Navy's Oceanographic and Atmospheric Research Lab in Monterey, Calif., then as a meteorological officer aboard the USS Nassau from 1981-83. During this latter assignment, Runco was designated a Naval Surface Warfare Officer. He then worked as a laboratory instructor at the Naval Postgraduate School and performed hydrographic and oceanographic surveys of the Java Sea and Indian Ocean, aboard the naval survey vessel Chauvenet. Selected by NASA in June 1987, Runco's police background led to the nickname of "Trooper." He had flown twice aboard the shuttle, firstly as a crewman on STS-44 and more recently with Casper on STS-54.

Over the next two days, following the IAE deployment, Endeavour remained at a distance of 55-70 miles (90-110 km) from SPARTAN-207, which also carried a payload of other technology experiments, including a new solid-state recorder and advanced integrated circuits in several of its electronics boxes. By the evening of 20 May, a few hours after deployment, the discarded IAE was being tracked at a distance of more than 115 miles (185 km) "ahead" and "below" the shuttle, and although its large size and relatively low weight made it difficult for trajectory specialists to predict exactly how long it would remain in orbit, they anticipated no longer than 17-24 hours. As circumstances transpired, IAE re-entered the upper atmosphere and burned up early on the 22nd, the same day that Casper and his men re-rendezvoused with SPARTAN-207 to begin retrieval activities.

The circular expanse of the Inflatable Antenna Experiment (IAE) is juxtaposed over Earth in the STS-77 crew's official patch. Image Credit: NASA

Awakened from their slumbers that morning to the sound of Fifth Dimension's song Up, Up and Away, in honor of their completed experiment, the astronauts wasted no time preparing their equipment for the rendezvous. In a similar manner to the approach procedures followed by several earlier shuttle crews, a Terminal Initiation (TI) burn of Endeavour's RCS thrusters kicked off the final approach and Casper guided his ship to just 35 feet (10 meters) from SPARTAN-207, whereupon astronaut Marc Garneau—who in October 1984 had become the first Canadian in space—extended the Canadian-built RMS arm and grappled the satellite at 10:53 a.m. EDT. As the satellite hung on the end of the arm, the crew performed a video and photographic survey, before it was berthed in the payload bay.

All six astronauts were intimately involved in the SPARTAN-207 rendezvous, including pilot Curtis Lee Brown Jr. and flight engineer Daniel Wheeler Bursch, both of whom were on their third shuttle missions. Brown hailed from Elizabethtown, N.C., where he was born on 11 March 1956. "My dream as a small kid was to fly," he once said. "I fell in love with aircraft and flying movies and things about flight and built all the little airplanes that kids always did when I was growing up." After completing high school in his hometown, Brown entered the Air Force Academy to study electrical engineering and earned his degree in 1978. He was commissioned as a second lieutenant and underwent flight instruction at Laughlin Air Force Base in Texas, later flying A-10 Thunderbolt aircraft in South Carolina. Brown's work subsequently earned him a position as an instructor pilot on the A-10 at Davis-Monthan Air Force Base in Arizona. Graduation from the Air Force's Fighter Weapons School at Nellis Air Force Base in Nevada in 1983 was followed by duties as an A-10 weapons and tactics instructor. He was selected for Test Pilot School at Edwards Air Force Base in June 1985, and, upon completion of this rigorous and demanding course, in mid-1986 he worked as a test pilot for the A-10 and the F-16 Falcon until his selection as an astronaut candidate in June 1987. Almost a decade later, at the time of STS-77, Brown already had two space missions under his belt as a pilot, and by the end of his NASA career in December 1999 he became the first person to have served six times as a shuttle pilot or commander. It is a distinction that, even today, after the retirement of the orbiters, he shares with only one other U.S. astronaut, Jim Wetherbee.

As Mission Specialist Two, Bursch supported Casper and Brown during ascent, re-entry, and throughout STS-77′s rendezvous activities. Earlier in his career, he had also earned the unenviable reputation of having endured two harrowing on-the-pad aborts for both his first and second space missions. Bursch was born on 25 July 1957 in Bristol, Penn., and studied physics at the Naval Academy. Upon graduation in 1979, he became a naval flight officer and trained as a bombardier/navigator in the A-6E Intruder. Overseas deployments followed to the Mediterranean aboard the USS John F. Kennedy and to the North Atlantic and Indian Oceans aboard the USS America, and upon his return to the United States he was selected for Naval Test Pilot School. Completion of the course in December 1984 was followed by A-6 test work and later duties as a flight instructor. He also served again overseas as Strike Operations Officer aboard the USS Long Beach and USS Midway and was in the process of completing his master's degree in engineering science at the Naval Postgraduate School when selected as an astronaut in January 1990. He flew aboard STS-51 in September 1993 and STS-68 in September 1994, both of whose inaugural launch attempts were stalled in the final seconds of the countdown, and after the ignition of the shuttle's main engines. Fortunately, Bursch's run of cruel fortune appeared to end on his third mission and STS-77 ran like a charm.

With the successful retrieval of SPARTAN-207, the shuttle's mission was barely a quarter complete, but its wide range of scientific and technological experiments were well underway. Flying for the fourth time as a research facility on STS-77, the commercial Spacehab was not dissimilar in appearance to the European Space Agency's (ESA) Spacelab module, but with several key differences: It was smaller, consuming just a quarter of the payload bay, and it was designed and built not by governments, but by private enterprise. It also differed from Spacelab in overall physical shape; it was cylindrical, but with a flat roof. When the module rose from Earth for the first time aboard STS-57 in June 1993, it marked the culmination and realisation of a decade-long dream for aerospace engineer Bob Citron, who founded the Spacehab company in 1983 and incorporated it the following year.

STS-77′s primary cargoes dominate this view of Endeavour's payload bay in orbit. In the foreground is the Spacehab-4 module, with SPARTAN-207 visible in the background. Photo Credit: NASA

"People often ask me why I started Spacehab," Citron recalled on the website www.astrotech.com, "and my response usually goes something like this: It took a small group of wide-eyed dreamers and determined space enthusiasts who believed we could pull it off. We didn't have a clue about the enormous problems we would encounter and the nearly insurmountable technical, financial and institutional roadblocks that would stand in our way. Nobody had done anything like this before." The primary goal of Citron, who died from prostate cancer in January 2012, was to create the world's first privately funded company to support human space missions, using the cavernous payload bay of the shuttle as a carrier of commercial pressurised research modules.

The need for such provision was self-evident. In the shuttle's pre-Challenger heyday, many missions were planned each year and a primary thrust of the Reagan Administration's 1983 space policy was for the commercial exploitation of the microgravity environment. Already, middeck lockers were being used to carry out experiments in crystal growth and pharmaceutical development, but the limited volume meant that their commercial viability was restricted. The Spacehab module, accessed, like Spacelab, by a tunnel adapter connected to the middeck airlock hatch, measured 9.2 feet (2.8 meters) long, 11.2 feet (3.4 meters) high, and 13.4 feet (4.1 meters) across the width of the payload bay and could increase the shuttle's pressurized research volume by almost 1,100 cubic feet (31 cubic meters), effectively quadrupling the available working and storage space. The module, which weighed approximately 9,480 pounds (4,300 kg) and could house a total payload of more than 2,870 pounds (1,300 kg), provided environmental provisions, electrical power, temperature control, and experiment command and data functions. It could carry a maximum of 61 middeck-sized lockers and up to two large racks, in either "single" or "double" configurations.

After incorporating Spacehab in 1984, Citron admitted that the company was "on the verge of failure on a number of occasions during its first years," until he brought in critical professional management personnel and "things started to happen" through negotiations with NASA, the Italian Alenia Spazio and German MBB-Erno organisations, and Martin Marietta and McDonnell Douglas. By the end of 1985, only weeks before the Challenger tragedy, Spacehab was tentatively scheduled for its first flight in 1987, and a lease of $5 million per mission was quoted by Flight International. Early plans called for the assembly of three modules, but center-of-gravity issues gave NASA cause for concern and threatened to affect the placement of other cargoes in the payload bay.

Ultimately, McDonnell Douglas was selected as the lead contractor and a decision was made to build two flight modules and an engineering test model. Other worries lingered, but in late 1986 Spacehab signed a Space System Development Agreement, in which NASA agreed to fly five inaugural missions. By October 1987, 42 firm requests had been received, with lockers priced at $300,000 for non-government users and $100,000 for government agencies and contractors. The concept was now growing from initial designs into reality. In September 1989, Patent No. 4,867,395 for a "Flat End-Cap Module for Space Transportation System" was awarded to Spacehab, Inc., by the U.S. Patent Office.

Mario Runco is pictured at work aboard Endeavour. Photo Credit: NASA

Hopes to fly the modules on very early post-Challenger missions received a rude awakening, however, and it was expected to be at least three years after the resumption of shuttle operations before a first flight could be realistically expected. According to NASA's April 1988 schedule, Spacehab-1 was listed as a primary payload on STS-51 in June 1991, co-manifested with the retrieval of Europe's EURECA free-flyer and the deployment of Italy's LAGEOS-II satellite. This schedule slipped and, at length, the first module was not unveiled until early 1992 at the custom-built Spacehab Payload Processing Facility (SPPF) at the Kennedy Space Center (KSC) in Florida. By this time, under the Commercial Middeck Augmentation Module procurement, initiated in February 1990 and formally signed the following December, NASA had agreed to lease a total of 200 Spacehab lockers at a cost of $184.2 million. Over the coming years, the SPPF would host more than a hundred astronauts and cosmonauts, enabling them to train on real experiment hardware.

However, all was not smooth sailing for Spacehab, which supported three dedicated science missions between June 1993 and February 1995 and was embarking on its fourth "stand-alone" flight on STS-77. In the aftermath of the first flight, however, few contracts outside NASA materialized for the laboratory, in spite of aggressive efforts to market its capabilities. This was due to a number of factors, chiefly high Spacehab locker prices in the region of $925,000 and anticipated commercial prospects failing to materialize. "No commercial companies are ready yet to make an independent commitment to research," said Rebecca Gray, Spacehab's manager of government and public relations, in a Flight International interview in late 1995, despite the company having delivered its services on time and on budget.

NASA's contract was renegotiated to cover four missions, of which STS-77—whose module, though full, was dominated almost exclusively by NASA-funded experiments—was to be the last. "If NASA requires more flights of this nature," Flight International continued, "it is likely only to be at a rate of about one flight a year and another contract will have to be negotiated." The company had already signed a $54 million lease contract with NASA to utilise its modules for logistics, rather than experiments, on several missions to Russia's Mir space station in 1996-98. It also invested $15 million of its own capital to develop a "double" logistics module to be used "as a laboratory and a cargo carrier," with the capacity to transport up to 6,000 pounds (2,720 kg) of payloads to Mir, as well as soft-stowage canvas bags for supplies. However, in the coming years, the option for more "stand-alone" research missions would be renegotiated and two would be flown, including STS-107, the final voyage of Columbia.

More than 90 percent of the Spacehab-4 payloads were directly sponsored by NASA's Office of Space Access and Technology (OSAT), through its Commercial Space Centers and their industrial partners, as well as by several of the agency's field centers. Right from the outset, STS-77 was dedicated to opening the commercial frontier of space, with the Spacehab module hosting almost 3,000 pounds (1,400 kg) of equipment in 28 lockers, four soft stowage bags, and a pair of single racks to support around a dozen investigations in the fields of biotechnology, electronic materials, polymers, and agriculture. These included the Advanced Separation Process for Organic Materials (ADSEP) to demonstrate separation and purification technologies for potential medical and pharmaceutical applications, the Commercial Generic Bioprocessing Apparatus (CGBA), and Plant Generic Bioprocessing Apparatus (PGBA) to investigate the influence of microgravity on molecular, cellular, tissue, and small animal and plant systems, as well as studying compounds which might someday prove beneficial as chemotherapy and anti-malaria agents and the Fluids Generic Bioprocessing Apparatus (FGBA) to explore the management of liquids in space.

The latter received corporate sponsorship from the Coca-Cola Company, which flew both Coke and Diet Coke aboard STS-77. The experiment, noted NASA, "will provide a testbed to determine if carbonated beverages can be produced from separately stored carbon dioxide, water and flavoured syrups and determine if the resulting fluids can be made available for consumption without bubble nucleation and resulting foam formation." If so, it was hoped that such experiments might lead to a better understanding of altered tastes in target populations, such as the elderly, and how future drinks could be tailored to increase hydration. International co-operation on STS-77 was underpinned by the presence of the Commercial Float Zone Furnace (CFZF), a joint effort between the respective space agencies of the United States, Canada, and Germany to produce large, ultra-pure compound semiconductor and mixed-oxide crystals of gallium arsenide and gallium antimonide for electronic devices and infrared detectors. Another payload, the Space Experiment Facility (SEF), used a furnace to produce through vapour-diffusion a series of crystals of mercurous chloride, which is considered a valuable electro-optical material of commercial interest, and to bond powdered metals through the liquid-phase sintering process, as part of efforts to design new composites for the machine tool industry.

STS-77 was shaping up to be not only an ambitious mission in space science and technology, but as an important demonstrator of the shuttle's myriad capabilities as a research platform, as a satellite deployment and retrieval facility, and as full-up precursor for the kind of work which would someday become "routine" aboard the International Space Station (ISS).

 

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AmericaSpace

For a nation that explores
May 25th, 2014

Mission for Science and Technology: 18 Years Since STS-77 (Part 2)

By Ben Evans

 

Fully deployed, the Inflatable Antenna Experiment (IAE) sprouts from the SPARTAN-207 satellite. Photo Credit: NASA

Eighteen years ago this week, six men orbited Earth aboard Shuttle Endeavour on one of the most complex research flights ever conducted in the program's 30-year history. With such a large number of payloads aboard, it was imperative for the STS-77 crew to begin activating as many experiments as possible on the first day of their planned 10-day flight. As described in yesterday's AmericaSpace history article, STS-77 was tasked with a multitude of experiments in the commercial Spacehab-4 laboratory and the deployment and retrieval of as many as four free-flying satellite payloads. Launch was originally targeted for 16 May 1996, but was pushed back to the 19th, since the earlier date was not available to NASA on the Eastern Range schedule. Commander John Casper, pilot Curt Brown, and mission specialists Andy Thomas, Dan Bursch, Mario Runco, and Canada's Marc Garneau had been training for the mission for almost a year, having been assigned in June 1995, and took their seats aboard Endeavour for a rousing, early-morning liftoff at 6:30 a.m. EDT.

Shortly after entering orbit and doffing their pressure suits, the six men set to work. In spite of a problem with a cooling device for one of the orbiter's hydraulic power units, Thomas and Garneau opened the hatch into the Spacehab module, floated inside, and began powering up experiments. Later in the day, Thomas also checked out the shuttle's Canadian-built Remote Manipulator System (RMS) mechanical arm, ahead of the deployment of their SPARTAN-207 satellite payload.

As the only first-time spacefarer on STS-77 crew, Andrew Sydney Withiel Thomas served as the payload commander, with overall responsibility of all of the mission's research objectives and science goals. Born in Adelaide, South Australia, on 18 December 1951, Thomas' father would later recount that his son became fascinated by space exploration as a child and built a steady stream of model rockets from cardboard and plastic. He received much of his early schooling in Adelaide, then earned a first-class degree in mechanical engineering from the University of Adelaide in 1973 and stayed on to pursue his PhD. "As a young kid, growing up in Australia, the likelihood of me being selected as an astronaut was pretty thin," Thomas told a NASA interviewer, "and I didn't really consider it a very realistic possibility." In his mind, the power of gaining a good education was the fundamental cornerstone, coupled with a conscious effort to steer his subsequent career goals toward the space programme. "I took steps in my career that would give me exposure to the right kinds of technical problems and technical experiences," he said, "which would make me a good candidate for an astronaut position." In 1977, shortly before receiving his doctorate, Thomas became a research scientist with the Lockheed Aeronautical Systems Company, with responsibility for investigations into the control of fluid-dynamic instabilities and aircraft drag. He was promoted to Principal Aerodynamic Scientist in 1980 and accepted the headship of the Advanced Flight Sciences Department in 1983, overseeing a group which explored problems in advanced aerodynamics and aircraft flight testing.

With a keen eye on joining NASA as an astronaut, Thomas became a naturalized U.S. citizen in December 1986, became the manager of Lockheed's Flight Sciences Division the following year and in 1989 moved to Pasadena, Calif., to join the Jet Propulsion Laboratory (JPL), later rising to become supervisor of the Microgravity Research Group. Three years later, in March 1992, he was selected by NASA as an astronaut candidate. His lifelong dream had been realised, and all due to the power of education. Thomas' attitude was that education opened a path to many of his life experiences. "In fact," he concluded, "it can open doors that you can't even imagine and that would remain forever closed."

The STS-77 crew. Seated are John Casper (right) and Curt Brown (left), with Dan Bursch, Mario Runco, Marc Garneau, and Andy Thomas standing. Photo Credit: NASA, via SpaceFacts.de

Flying in space for the first time on STS-77 was a totally new path for Andy Thomas, even when placed alongside many of the challenges he had overcome on Earth. "And although the environment is totally alien and unnatural, your body starts to accept it as being natural and psychologically you accept it as being natural," he said. "You start to feel that being weightless is just the normal way to be; that everything does float and that you float. It's just the amazing adaptability of the human body. Of course, the down side to that is when you come back, you have to re-educate your body to working in gravity. You feel all your internal organs being pulled down, your arms being pulled down, your head being pulled down and you stand up and just feel this ponderous mass of your entire body. It gives you a perspective on gravity … that people just generally never get unless you go through that. You realize just what a demanding force it actually is."

In Endeavour's middeck, the Immune-3 experiment tested the ability of insulin-like growth factor to prevent or reduce the detrimental effects of microgravity exposure on the immune and skeletal systems of rats, whilst three investigations sought to crystallize various protein crystals with objectives to address a range of diseases and the Gas Permeable Polymer Membrane (GPPM) pioneered the development of enhanced polymers for manufacturing rigid gas-permeable contact lenses. The National Institutes of Health provided a tissue culture incubator, and its experiments focused on the influence of weightlessness on the muscle and bone cells of chicken embryos. Elsewhere, the metamorphosis of tobacco hornworm was examined, as part of efforts to understand the synthesis of muscle-forming proteins,   the processes of fertilisation, and embryonic development of small aquatic organisms, including starfish, mussels, and sea urchins. In fact, the latter was one of the first experiments to be activated by Mario Runco, a few hours after liftoff.

With such substantial involvement from Canada, it seemed unsurprising that STS-77 featured a Canadian astronaut as one of its four mission specialists. In fact, Joseph Jean-Pierre Marc Garneau became Canada's first man in space when he served as a payload specialist aboard shuttle mission STS-41G in October 1984. He came from Quebec City, where he was born on 23 February 1949. His father was an army officer "and we traveled quite a bit when I was growing up," he told a NASA interviewer, "and I thought that I would like to have a military career, although I was drawn more towards the Navy." Garneau would explain this decision in just three words: love of adventure. He was educated in Quebec and received his degree in engineering physics from the Royal Military College of Canada in Kingston in 1970. Garneau traveled to England in pursuit of his doctorate, studying electrical engineering at the Imperial College of Science and Technology in London. After gaining his PhD in 1973, he joined the Canadian Forces Maritime Command as a Navy engineer, serving aboard HMCS Algonquin and later as a forces fleet school instructor. During this period, Garneau designed a simulator to train weapons officers to use the missile systems aboard Tribal-class destroyers. Whilst at staff college in 1982, he was promoted to the rank of commander in the Canadian Navy. He was transferred to Ottawa the following year to design naval communications and electronic warfare systems and equipment.

In December 1983 he was selected as an astronaut candidate, and in February he was seconded from the Department of National Defence to commence full-time training. Following his first shuttle mission, Garneau was promoted to captain in the Navy and retired from active military service in 1989 to become deputy director of the Canadian Astronaut Programme (CAP). In mid-1992, alongside fellow Canadian Chris Hadfield, he was selected by NASA for mission specialist training.

STS-77′s primary cargoes dominate this view of Endeavour's payload bay in orbit. In the foreground is the Spacehab-4 module, with SPARTAN-207 visible in the background. Photo Credit: NASA

If Endeavour's crew cabin and the Spacehab module both represented a hive of activity during STS-77, then the payload bay was similarly packed with experiments. The Brilliant Eyes Ten Kelvin Sorption Cryocooler Experiment (BETSCE) was carried as part of ongoing efforts to develop technologies to rapidly cool infrared and other sensors to near-absolute zero Kelvin (-273.15 degrees Celsius). The aim of BETSCE was to employ a highly reliable "sorption cooler," which exhibited virtually no detrimental effects of vibration, to cool infrared sensors to just 10 degrees Kelvin (-263.1 degrees Celsius). "Sorption coolers work by using specialised metal alloy powders, called metal hydridges, that absorb the hydrogen refrigerant through means of a reversible chemical reaction," NASA explained in its STS-77 pre-flight press kit. "In the sorption compressor, the metal powder is first heated to release and pressurise the hydrogen, and then cooled to room temperature to absorb hydrogen and reduce its pressure. By sequentially heating and cooling the powder, the hydrogen is circulated through the refrigeration cycle. Ten degrees Kelvin is achieved by expanding the pressurised hydrogen at the cold tip of the refrigerator. This expansion actually freezes the hydrogen to produce a solid ice cube. The heat load generated by the device being cooled then sublimates the ice. This closed-cycle operation is repeated over and over."

Previous astronomy missions which conducted their studies in the infrared needed to carry large, heavy, and expensive dewars of liquid helium or hydrogen to accomplish operating temperatures as low as 10 Kelvin, but the duration of their useful lives were restricted when the cryogens eventually boiled off and ran out. "The ability to achieve a lifetime of ten or more years, with no vibration," NASA added, "opens the door to a wide variety of future missions that could benefit from this novel technology."

Mounted atop a Hitchhiker structure in Endeavour's payload bay was the Technology Experiments for Advancing Missions in Space (TEAMS), provided by NASA's Goddard Space Flight Center (GSFC) of Greenbelt, Md., which featured four investigations: the GPS Attitude and Navigation Experiment (GANE) to gauge the effectiveness of Global Positioning System technology, which was then in its infancy, the Vented Tank Resupply Experiment (VTRE) to evaluate improved methods for refueling in space, the Liquid Metal Thermal Experiment (LMTE) to test potassium-filled liquid metal heat pipes in microgravity, and the Passive Aerodynamically Stabilized Magnetically Damped Satellite-Satellite Test Unit (PAMS-STU). The latter was of particular interest on STS-77, for its presence led the mission to establish a new record as the first shuttle flight to complete as many as four separate rendezvous operations. Developed by NASA-Goddard, PAMS-STU was a technology demonstrator for the principle of natural "aerodynamic stabilization," which it was hoped might increase the orbital lifetime of satellites by reducing or eliminating the need for large quantities of attitude-control propellants. "Aerodynamic stabilisation works the same way as a dart," NASA explained shortly before the STS-77 launch. "The front of the dart is weighted and once the dart is thrown, it will always right itself with the head facing forward. In the same manner, the PAMS-STU satellite will eventually be oriented with the heavy end facing forward in orbit. This principle can be used to partially control the attitude of small satellites."

Within sight of the giant Vehicle Assembly Building (VAB), Endeavour touches down at the Kennedy Space Center (KSC) on 29 May 1996. Photo Credit: NASA

On the fourth day of the mission, 22 May 1996, the PAMS-STU operations got underway when Runco deployed the cylindrical, 2 x 3 foot (60 x 90 cm) satellite at 5:18 a.m. EDT from a canister at the rear end of Endeavour's payload bay.  As intended, it drifted away from the orbiter in a rotating, unstable attitude, in order to evaluate how quickly and effectively it could stabilise itself using natural aerodynamics. Casper and Brown maneuvered the shuttle to a distance of nine miles (14.6 km) to begin the first of three scheduled rendezvous exercises. A little over 4.5 hours later, they drew closer to about 1,970 feet (600 meters) to track PAMS-STU with the laser-based Attitude Measurement System (AMS) in the payload bay. However, it was noticed that the satellite had not yet stabilized itself and a strong "lock" could not be obtained. With two further rendezvous sessions, each lasting around 6.5 hours, planned for 24 and 25 May, Endeavour withdrew to a maximum distance of about 64 miles (103 km).

During their second rendezvous on 24 May, Casper and Brown reached a station-keeping point just 1,700 feet (520 meters) from PAMS-STU and held their position for more than six hours, until a problem arose with the Space Experiment Facility (SEF) in the Spacehab module and Andy Thomas was called away to commence troubleshooting. It was clear from video imagery acquired by the crew that the satellite had begun to stabilize itself with natural aerodynamic forces, albeit somewhat slower than expected. The third and final rendezvous was postponed by 24 hours, until 26 May, in order for engineers to evaluate the AMS, which provided high-accuracy data (to within one-tenth of a degree) on the behavior and relative motions of PAMS-STU. Although it had proven its ability to track the small satellite, the laser system seemed to be locking onto an unknown target (perhaps a structure in the payload bay) and was subjected to intensive troubleshooting.

Throughout those 24 hours, Endeavour moved away from the satellite, reaching a maximum distance of about 115 miles (185 km), before Casper executed a Reaction Control System (RCS) thruster firing on the 26th to begin the third period of rendezvous. Closing on PAMS-STU at about 2.3 miles (3.7 km) per orbit, this time the operation ran by the book, with Casper and Brown guiding their ship to within 1,800 feet (550 meters) of their quarry. As the orbiter's payload bay faced the satellite, NASA-Goddard flight controllers successfully commanded the AMS to calculate its attitude to within one-tenth of a degree. The pilots moved closer, to just 1,640 feet (500 meters), and held their position for seven hours and 45 minutes. This was about 70 minutes longer than planned, as controllers verified that the AMS laser was impinging on PAMS-STU's reflectors. Throughout the third rendezvous, the satellite remained very stable and validated the aerodynamic stabilization concept.

Departing PAMS-STU for the final time, the STS-77 crew entered the final days of their mission, heading for a landing at the Kennedy Space Center (KSC) in Florida on 29 May 1996. It was expected that the small satellite would re-enter the upper atmosphere to destruction after a few weeks, although trajectory specialists noted that it might remain aloft until as late as January 1997. (As circumstances transpired, PAMS-STU ended its days on 26 October 1996.) Weather forecasts at KSC and Edwards Air Force Base, Calif., were highly favourable for an on-time landing, with two opportunities available at each site on the 29th. The first opportunity to land in Florida was taken, and Casper executed the de-orbit burn at 6:09 a.m. EDT and guided his ship to a smooth touchdown on Runway 33, precisely an hour later, at 7:09 a.m. With more than 21 cumulative hours of formation flying, Endeavour's crew had secured a new record for themselves by becoming the first mission to execute four discrete periods of rendezvous. STS-77 also marked the first shuttle flight to be powered into orbit by a full set of three Block I main engines and the first to be fully controlled from the new Mission Control Center (MCC) at the Johnson Space Center (JSC) in Houston, Texas.

 

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