Footsteps to Mars (1993)

The ungainly contraption pictured above is a piloted Mars lander based partly on planned Space Station Freedom hardware. Boeing proposed the design in 1990 as part of President George H. W. Bush's failed Space Exploration Initiative. Image: Boeing/NASA.

The Space Exploration Initiative (SEI), launched by President George H. W. Bush amid great fanfare on the steps of the National Air and Space Museum on the 20th anniversary of the Apollo 11 Moon landing (20 July 1989), was seen by many space supporters as a new Apollo Program. Nothing, however, could have been farther from the truth.

Apollo fulfilled a perceived national need: specifically, to assert U.S. technological primacy in the Cold War with the Soviet Union. SEI, by contrast, seemed to fulfill no purpose commensurate with its projected cost. President John F. Kennedy called for Apollo at the Cold War's height; Bush proposed SEI as the Eastern Bloc disintegrated. Though Bush, a Republican, apparently felt genuine enthusiasm for space exploration, he distanced himself from SEI by the beginning of 1991, when it had become an obvious political liability.

The initiative continued with minimal funding until Democratic President William Jefferson Clinton took office in January 1993. By May of that year, when the Case for Mars V conference convened in Boulder, Colorado, NASA's Moon and Mars exploration planning apparatus was in the process of being dismantled. The Case for Mars V became SEI's wake.

Geoffrey Landis, a NASA Lewis Research Center (now NASA Glenn Research Center) engineer and award-winning science-fiction author, presented a plan for recovery from SEI at The Case for Mars V. He subsequently published it in The Journal of the British Interplanetary Society. He began his paper by declaring that SEI was "politically dead" — it had, he wrote, come to be "viewed as an expensive Republican program with no place in the current era of deficit reduction." Landis then asked, "how can we advocate Mars exploration without appearing to be attempting to revive SEI?"

Landis's solution was a new piloted Mars program that would take into account lessons taught by Apollo ("If you accomplish your goal, your budget will be cut") and the Space Shuttle ("if you do the same thing over and over, the public will focus on your failures and forget your successes"). The Landis program was a 14-year series of incremental "footsteps" which, he said, would be in keeping with NASA Administrator Dan Goldin's "faster, better, cheaper" philosophy of spaceflight (at the time of The Case for Mars V, this philosophy was still in its infancy). The footsteps would, he argued, provide a series of interesting milestones that would maintain public enthusiasm for the program at least until a piloted Mars landing took place.

Landis's first footstep, which he optimistically asserted could occur "immediately," was a piloted Mars flyby mission based on existing U.S. and Russian launch vehicles and space station hardware. The 18-month mission would test a potential design for a piloted Mars transfer vehicle and demonstrate long-duration interplanetary flight and high-speed Earth-atmosphere reentry.

While close to Mars, the astronauts would take advantage of short radio signal travel time to teleoperate a rover on the planet. The rover would be launched to Mars on a separate launch vehicle ahead of the piloted flyby spacecraft. Teleoperations would enable planetary quarantine to be maintained until the debate over whether life exists on Mars could be resolved.

The second footstep in the Landis plan would be a piloted landing on Deimos. Landis noted that, with the possible exception of a few near-Earth asteroids, Mars's outer moon was the most accessible object beyond Earth orbit in terms of the amount of energy required to reach it. The mission would demonstrate Mars orbit insertion, Mars orbital operations, and Mars orbit departure. Deimos, Landis added, might contain water that could be split using electricity into hydrogen and oxygen, which could serve as chemical rocket propellants.

The third footstep was a piloted landing on Phobos, Mars's inner moon. "From Phobos," Landis declared, "the view of Mars will be spectacular." He proposed that an unmanned version of the piloted Mars lander be test-landed on Mars during the Phobos expedition. The lander might be used to collect a Mars surface sample and blast it back to Phobos for recovery by the astronauts and return to Earth laboratories for analysis.

Boeing design for a nuclear-thermal-propulsion piloted Mars spacecraft based on Space Station Freedom hardware heritage. The large round bowl at left is the heat shield for one of the mission's two piloted Mars landers, which nestles in the bowl. The lander is depicted on the surface of Mars in the image at the top of this post. An ascent stage from another Mars lander is about to dock. The ascent stage is shown in more detail in the image near the bottom of this post. Boeing proposed this inelegant design during 1990 for President George H. W. Bush's abortive Space Exploration Initiative. Image: Boeing/NASA.

Landis's fourth footstep would encompass several piloted Mars lander tests in Earth orbit and on the Moon (incidentally returning Americans to the Moon for the first time since Apollo 17 in December 1972). This would set the stage for the fifth footstep, a piloted landing during summer on one of Mars's polar ice caps.

Landis wrote that the martian ice caps contained readily accessible water that could be melted and split into hydrogen and oxygen propellants. In addition, the summer pole would receive continuous sunlight. Landis, a space power system engineer, noted that this would make highly efficient the use of electricity-generating solar arrays. Because the Sun would not set, the expedition would need neither batteries nor the extra solar arrays required to charge them for periods when the Sun was below the horizon.

The Mars temperate landing, the sixth footstep, would mark the culmination of Landis's program. Successfully accomplishing a landing in the martian mid-latitudes would, Landis predicted, result in budget cuts and Mars program cancellation within two years.

His seventh footstep was, thus, designed to postpone the inevitable. He argued that a landing in Valles Marineris, the equatorial "Grand Canyon" of Mars, would provide a spectacular coda exciting enough to forestall program cancellation.

Liftoff from Mars — time to slash the Mars program budget. Painted by Pat Rawlings for NASA, this image depicts the ascent stage of the Boeing-designed piloted Mars lander shown at the top of this post. Though Geoffrey Landis expected that Americans would support only two or three piloted Mars landing missions before they lost interest, this optimistic Space Exploration Initiative-era painting hints at an on-going piloted Mars program: shown on the surface are habitats, solar arrays, a tethered research balloon, and a nuclear plant.

Landis wrote that finding easily exploitable resources on Deimos, Phobos, and Mars might lower costs, enabling piloted Mars exploration to continue on "a shuttle-scale budget." He echoed science popularizer and planetary scientist Carl Sagan when he proposed that Mars replace the Cold War as a driver for Western aerospace, adding that the Soviet Union's collapse in 1991 had made available Russia — with its Energia heavy-lift rocket, Mir space station modules, and long-duration spaceflight experience — as a cooperative partner. Landis concluded by urging an immediate start to his Mars program, arguing that "despite indications, there is no better time to act."

Source

"Footsteps to Mars: An Incremental Approach to Mars Exploration," Geoffrey Landis, Journal of the British Interplanetary Society, Vol. 48, September 1995, pp. 367-372; paper presented at The Case for Mars V conference in Boulder, Colorado, 26-29 May 1993.

More Information

After EMPIRE: Using Apollo Technology to Explore Mars and Venus (1965)

Making Rocket Propellants from Martian Air (1978)

Bridging the Gap Between Space Station and Mars: The IMUSE Strategy (1985)

Could the Space Voyages in the Film and Novel "2001: A Space Odyssey" Really Happen? (Part 1)

An advanced LANTR Moon shuttle departs low-Earth orbit. Image credit: Pat Rawlings/NASA.

The film and novel 2001: A Space Odyssey changed my life. I know, that sounds overwrought, but it's true. I was six years old in April 1968, when the classic collaboration between science fiction author Arthur C. Clarke and film director Stanley Kubrick hit movie screens around the world. By that point in my young life, I had been reading for three years. I knew that I liked science — especially geology — so a "science fiction" film sounded intriguing.

By the time the movie drew to a close, I had become a spaceflight fan and a science fiction buff. I remain so afflicted today. (I expect that the existence of this blog makes the "spaceflight fan" part kind of obvious.)

The film 2001 is enigmatic, with mostly banal dialog and an ending that left many who saw it in its first run feeling confused and even cheated. Clarke's novel fills in gaps, but its narrative differs from the cinematic narrative. For example, in the movie 2001, Jupiter is the spaceship Discovery's destination; in the book 2001, the natural wonders of the Saturn system as understood in 1968 are used to good effect. None of this ambiguity troubled me; in fact, the mysteries stoked my young imagination.

Arthur C. Clarke (left) and Stanley Kubrick on the Aries-1B Moon shuttle passenger cabin set. Image credit: The Stanley Kubrick Archives.

This background explains why a pair of technical papers caught my attention as the year 2001 approached and passed. Nuclear propulsion engineers at NASA's Lewis Research Center (now Glenn Research Center) in Cleveland, Ohio, authored both papers. They described ways that the piloted spaceflight capabilities portrayed in the film and book 2001 might be made reality using technology and techniques that are either already in existence or are plausibly foreseeable.

In the first paper, first published in 1997 and subsequently lightly revised, Stanley Borowski and Leonard Dudzinski looked at how a 24-hour voyage to a lunar surface base might be accomplished using Nuclear Thermal Rocket (NTR) propulsion and liquid oxygen (LOX) mined from the Moon. For comparison, Apollo spacecraft needed more than three days to travel from Cape Kennedy to lunar orbit.

The second paper is much more ambitious, but also more speculative. It offers a design and operational scenario for a nuclear-fusion-propulsion spacecraft named Discovery II which could reach Jupiter orbit in just four months and Saturn orbit in seven. I will discuss it in my next two posts.

The film and book 2001 both begin with a band of man-apes who are having a tough time of it. They grub in the dust for bits of vegetation beside competing quadruped herbivores and huddle together at night listening to screeching big cats, for whom they make easy prey.

The book focuses on a hominid named Moonwatcher. Some time after an intellect-boosting encounter with an alien black monolith, he grasps the related concepts of tool-use and hunting. Soon his entire band wields bone clubs. They hunt the unsuspecting herbivores, drive off the big cats, and make war on a technologically backward rival band.

After murdering the rival band's leader, Moonwatcher of the film 2001 hurls his club triumphantly at the sky, where it becomes an Earth-orbiting satellite bearing nuclear warheads. In a heartbeat we leap over three million years of human evolution and technology advancement.

A more hopeful sign of advanced technology appears — a gleaming white space plane in Pan American Airlines livery. On board is Dr. Heywood Floyd, a high-level bureaucrat on a mission for the United States Astronautics Agency (USAA). National security, the novel 2001 explains, requires that he fly with only a pilot, co-pilot, and stewardess for company.

USAA is evidently a NASA successor organization. One can speculate that, in the 2001 timeline, a well-funded NASA worked with large commercial entities and handed off certain of its roles as, with NASA aid, those commercial entities succeeded in proving themselves capable of providing necessary spaceflight services. Along the way, NASA handed off aeronautical research (the first "A" in the acronym NASA) and became largely focused on advanced spaceflight development and scientific exploration. This prompted a name change.

The Pan Am space plane deposits Floyd at a wheel-shaped artificial-gravity international space station. It is the fifth in a series, so is called Space Station V. There Floyd confronts members of a rival band — a group of Soviet scientists on their way home from the Moon — and transfers to a near-spherical Aries-1B Moon shuttle to begin his journey to the U.S. base in 150-mile-wide Clavius crater.

Aries-1B Moon shuttle. Image credit: Turner Entertainment/Metro Goldwyn Mayer.

In the book 2001, the 30-passenger Moon shuttle's "low-thrust plasma jet" propulsion system operates for "more than 15 minutes" to begin the 25-hour voyage to the Moon. Floyd, alone on board with a pilot, co-pilot, steward, stewardess, and two engineers, hears the "whistling" of the "electrified" plasma jets. He feels the acceleration they impart to the Moon shuttle as a "mild" pressure pushing him down into his seat.

In their 1997 paper, Borowski and Dudzinski dubbed their Moon shuttle propulsion system LANTR, which stands for "LOX-Augmented Nuclear Thermal Rocket." They envisioned that LANTR propulsion would form a critical component of a cislunar transportation infrastructure that ultimately would include multiple interdependent vehicles and a Lunar Oxygen (LUNOX) mining and refining base near the Apollo 17 landing site at Taurus-Littrow on the southeast edge of Mare Serenitatis.

LUNOX, the NASA Lewis nuclear propulsion engineers explained, was likely to become the first large-scale space commodity. The "orange soil" Apollo 17 explorer Harrison Schmitt kicked up on the flank of Shorty Crater — which, it turns out, occurs at many places on the Moon — would, they estimated, make a rich feedstock for LUNOX refining, with every 25 tons of the volcanic glass-rich dirt collected and processed yielding a ton of LUNOX. For comparison, about 327 tons of more typical lunar surface material would need to be mined and refined to produce a ton of LUNOX.

The LANTR architecture, based on a NASA Lewis Nuclear Thermal Rocket (NTR) architecture developed for the abortive Space Exploration Initiative (1989-1993) of President George H. W. Bush, would evolve over time. It would not at first use LUNOX, reach the Moon in a day, or include reusable vehicles.

Borowski and Dudzinski sought to reduce the cost of their Earth-to-low-Earth-orbit (LEO) launches by exploiting then-existing Space Shuttle hardware and facilities. A pair of Shuttle-Derived Launch Vehicles (for example, Shuttle-C), each capable of placing a 66-ton payload into 407-kilometer-high LEO, would suffice to launch an expendable "two-tank" NTR stage, expendable piloted lunar spacecraft, and cargo.

Shuttle-C in its most basic form: an expendable cargo canister with a two-engine Shuttle boat-tail replaces the Space Shuttle Orbiter. Image credit: NASA.

The first Shuttle-C payload, the 24-meter-long "core stage," would comprise a pair of NTR engines, attitude control and docking systems, and a 7.6-meter-diameter, 17.5-meter-long insulated, meteoroid-shielded tank with 49.3 tons of cryogenic liquid hydrogen (LH2) inside. The engines would serve as both electricity generators and rocket motors. Because they would have two roles, or "modes," Borowski and Dudzinski dubbed them Bimodal Nuclear Thermal Rocket (BNTR) engines.

The BNTR engine's basic design would resemble that of NTR engines going back to the 1950s. LH2 would serve double duty as nuclear-fission reactor coolant and rocket propellant. After passing through and cooling the reactor, the hydrogen, now hot and gaseous, would vent into space through a bell-shaped nozzle to produce thrust.

The second Shuttle-C payload would comprise a 4.6-meter-diameter, nine-meter-long tank with nine tons of LH2, an adapter for linking with the core stage, and a conical crew capsule with four astronauts on board. It would also include a second spacecraft: a 44-ton LH2/LOX chemical-propulsion Lunar Landing Vehicle (LLV) with a five-ton crew cabin and nine tons of cargo bound for the lunar surface.

The two Shuttle-C payloads would dock in LEO, forming what Borowski and Dudzinski called a Lunar Transfer Vehicle (LTV). With the LLV attached, it would measure 46 meters in length. Its twin BNTR engines would heat and expel LH2 for 47.5 minutes to place the LTV/LLV combination on course for an Earth-moon voyage lasting 84 hours.

At the end of this cislunar journey, the BNTR engines would fire a second time so that the Moon's gravity could capture the LTV/LLV combination into 300-kilometer-high orbit. The crew would board the LLV and descend to the lunar surface with their nine tons of cargo, which would include equipment for mining, refining, and storing LUNOX, as well as scientific gear and lunar base components.

The crew would spend 45 days on the Moon living out of the LLV. They would then pilot the LLV back to lunar orbit, transfer to the LTV capsule, cast off the spent LLV, and fire the BNTR engine pair to depart lunar orbit for an 84-hour journey to Earth.

Near Earth, the crew capsule would detach from the LTV and reenter the atmosphere directly. The rest of the LTV would swing by Earth and fire its BNTR engines briefly to boost itself into a Sun-centered disposal orbit. In total, the LTV BNTR engines would operate for 61.4 minutes during a 54-day round-trip lunar mission.

Borowski and Dudzinski also described one-way cargo missions derived from their piloted architecture. Twenty-five tons of additional cargo would replace the crew cabin and propellants for boosting the LLV back to lunar orbit, bringing total cargo delivered to the Moon's surface to 34 tons.

LUNOX production would ramp up with each successive expendable LTV/LLV lunar mission. In lockstep with the increasing supply of LUNOX, NASA would upgrade the cislunar transportation system so that, after an unspecified number of flights, it would evolve into Borowski and Dudzinski's reusable LANTR architecture. The LANTR architecture would, they explained, support routine weekly 24-hour Earth-Moon "commuter" flights.

By then, LUNOX production would amount to 10,878 tons per year. Of this, reusable Earth-bound LANTR LTVs would use 4888 tons, while reusable LLVs for transporting LUNOX, crews, and cargoes between the LUNOX surface base and a lunar orbit propellant depot would expend 5990 tons.

The NASA Lewis engineers assumed that 11 solar-powered, teleoperated LUNOX plants operating 35% of the time (this is, for 70% of each two-week lunar daylight period) could each strip-mine and refine 25,000 tons of orange soil to produce about 1000 tons of LUNOX per year. They estimated that the orange soil area near the Apollo 17 landing site might yield up to 700 million tons of LUNOX; that is, enough to support weekly 24-hour commuter flights for the next 60,000 years.

LANTR would see the basic all-LH2 BNTR engine augmented with a system for introducing LOX into the supersonic hot hydrogen exhaust flow "downstream" of the reactor. The LOX would enable the hydrogen to burn much as it does in a conventional LOX/LH2 chemical rocket engine, dramatically increasing LANTR thrust. This, Borowski and Dudzinski wrote, would offer "big engine" performance from "smaller, more affordable, easier to test NTR engines."

To trim development cost, the LANTR LTV would structurally closely resemble the all-LH2 LTV already described. At 7.5 meters long, the LANTR LTV's forward section would measure 1.5 meters shorter than its all-LH2 counterpart. The aft section, the core stage, would be outwardly identical to its all-LH2 predecessor. As with the all-LH2 LTV, a pair of Shuttle-Cs would launch the fore and aft sections of the LANTR LTV, which would then rendezvous and dock automatically in LEO.

The LANTR LTV would then dock automatically with a propellant depot in LEO. There it would fill its large tank with 45.5 tons of LH2 and its small tank with 112.3 tons of LOX, which is much denser than LH2. The propellant depot's LOX and LH2 would all be produced on Earth and boosted into LEO on Shuttle-derived launch vehicles.

Meanwhile, a Space Shuttle or a next-generation reusable piloted spacecraft would deliver to the International Space Station (ISS) 20 passengers bound for the LUNOX production base on the Moon. Accommodations on board the ISS are, of course, not spacious, so the new arrivals would immediately move into a 15-ton, 4.6-meter-diameter, eight-meter-long cylindrical Passenger Transport Module (PTM) docked with the station. Even in its most advanced form, Borowski and Dudzinski wrote, their Earth-Moon transportation system would be "spartan" compared with Heywood Floyd's Moon shuttle; it would, for example, not employ stewards.

The 20 Moon voyagers would remain inside the PTM throughout their 24-hour Earth-Moon journey, so would see little change in their immediate surroundings from the time they boarded it until they entered the lunar surface base. The PTM would, however, interface with three vehicles besides the ISS during each lunar flight.

As the time for LEO departure approached, the PTM would undock from the ISS and move away using its own chemical-propellant attitude-control thrusters. It would rendezvous with a LANTR LTV standing by near the LEO propellant depot at a "safe distance" from the ISS: that is, far enough away that radiation from its BNTR engines could neither harm the ISS crew nor reflect off ISS structure and harm the astronauts in the PTM. The PTM would approach and dock tail-first with the LANTR LTV, forming a 195.6-ton LANTR "commuter shuttle."

The commuter shuttle would climb away from LEO quickly (image at top of post). Acceleration to 24-hour Earth-Moon transfer velocity would need only 21.2 minutes, or less than half the duration of the all-LH2 LTV burn required to achieve an 84-hour Earth-Moon transfer. During the climb away from LEO, the 20 passengers would, much like Dr. Floyd in the book 2001, feel only a "mild" pressure — to be precise, just 0.23 Earth gravities of acceleration at BNTR start-up, when the commuter shuttle was fully loaded with propellants, and 0.46 gravities just before BNTR engine shutdown, when about half its propellants were expended.

Twenty-four hours after LEO departure, the BNTR engines would fire again to slow the commuter shuttle so that the Moon's gravity could capture it into lunar orbit. It would rendezvous with a lunar-orbit propellant depot containing LH2 brought from Earth and LUNOX.

The PTM would undock from the commuter shuttle and link up with a waiting lunar surface-based reusable LLV, the second vehicle with which it would interface during its trip to the Moon. The skeletal four-engine LLV would weigh 10.9 tons without propellants or cargo and 59.5 tons loaded with 33.6 tons of propellants and the 15-ton PTM.

In lunar orbital night: at the end of a 24-hour Earth-Moon crossing, the PTM (lower left) has separated from the LANTR LTV (lower right) near the Moon-orbiting propellant depot (barely visible above the LANTR LTV). A reusable LLV now moves into position to grapple the PTM and begin descent to the LUNOX production base on the Moon's surface. Image credit: Pat Rawlings/NASA.

The LLV would descend to the LUNOX base on four plumes of burning Earth hydrogen and LUNOX. After touchdown, a wheeled flatbed — the third vehicle with which the passenger module would interface — would move into position beneath the PTM and detach it from the overhead LLV framework. The PTM/flatbed combination would then roll over the lunar surface from the landing field to an airlock leading into a surface habitat. After linkup with the habitat, the 20 passengers would exit the PTM to begin their duties on the Moon.

In addition to moving passengers and cargo between Earth and Moon and back again, the LANTR architecture would, as already indicated, move LUNOX and Earth-produced LH2. Four times per week a reusable tanker module with an empty weight of five tons loaded with 25 tons of LUNOX would ride a flatbed to a waiting automated LLV and then ascend to the Moon-orbiting propellant depot. After pumping its LUNOX cargo into the propellant depot's tanks, it would return to the LUNOX base.

Welcome to the Moon: in the lower right corner, a PTM rides a six-wheeled flatbed to an airlock leading into a large inflatable lunar surface habitat. Meanwhile, at upper center-right, a tanker LLV lifts off on a mission to transport LUNOX to the lunar-orbital propellant depot. Image credit: Pat Rawlings/NASA. 

Borowski and Dudzinski assumed a fleet of four LANTR LTVs. Each would carry out 13 Earth-Moon round-trips per year, for a total of 52 commuter flights (that is, one per week). Each LANTR LTV would in its BNTR engines hold enough fissile material to permit 44 Earth-Moon round-trips, giving it an operational lifetime of 3.3 years.

A LANTR LTV near end-of-life would perform a one-way all-cargo mission before disposal into a Sun-centered orbit. One-way cargo would include Earth-produced LH2 for the propellant depot in lunar orbit. With about 23 tons of surplus LH2 in its "core stage" tank, a one-way LOX load of only 66 tons, and a potential cargo weight of about 80 tons, the LANTR LTV might deliver more than 100 tons of LH2 to lunar orbit during its final mission.

When Borowski and Dudzinski wrote their paper in 1997, existence of lunar polar ice in permanently shadowed craters, first predicted in 1961, remained uncertain. Data from a 1994 joint experiment using the Clementine lunar orbiter and NASA's Deep Space Network antennas had hinted strongly at the existence of hydrogen at the poles, but alternate explanations for the hydrogen signal existed, and an experiment employing the giant Arecibo radio telescope in Puerto Rico could find no trace of lunar hydrogen.

Robotic spacecraft in lunar polar orbit have since confirmed that a large quantity of water ice exists at the Moon's poles — in the billions of tons. Provided that mining equipment can be designed to operate in the very cold, very dark environment of the permanently shadowed craters, the existence of water ice means that both oxygen and hydrogen await us on the Moon in potentially easily processed form.

In theory, water ice-rich feedstock need only be heated to separate out the water, which would then be split into hydrogen and oxygen using electrolysis. Though this would seem to render Borowski and Dudzinski's LUNOX mining scenario irrelevant, their LANTR-based transportation system might burn LOX and LH2 derived from lunar polar ice as easily as it could Earth LH2 and LUNOX.

Early drafts of the 2001: A Space Odyssey screenplay — there were many — are replete with informative dialog. Though actors spoke some of the dialog during filming, most was replaced with classical music and sound effects in the final film.

In a late 1965/early 1966 draft of the script, the Aries-1B moon shuttle pilot and co-pilot speculate about the purpose of Heywood Floyd's unprecedented single-passenger lunar flight. The pilot remarks that the Moon shuttle will return to Earth orbit without passengers because Clavius Base is under quarantine. Only Floyd would be permitted to leave the Moon shuttle and no one at the base  would be permitted to board it.

The co-pilot points out that Moon shuttle tickets cost $10,000 one-way, so Floyd's mission will cost USAA and U.S. taxpayers about $600,000 — that is, the same as a round-trip flight with 30 passengers on board going each way. Alas, Borowski and Dudzinski provided no estimate of the cost of reaching the Moon using their proposed infrastructure.

In the book 2001, Floyd disembarks from the Aries-1B and stops for a glass of lunar sherry — made from Moon-grown algae — in the Clavius Base Administrator's office. He then attends a briefing in which he hears the latest news about the find that motivated his secretive single-passenger Moon flight. A black monolith found beneath the floor of Tycho crater has, he learns, nothing to do with the Chinese expedition of 1998. It was, geologists from Clavius Base have determined, deliberately buried three million years ago. It is the first evidence of intelligent life off the Earth.

After a moonbus ride across the rugged southern Lunar Highlands to Tycho, Floyd witnesses the beginning of a slow lunar dawn. He dons an advanced space suit — doing so takes only a few minutes, and it barely restricts his movements — then descends into the pit excavated around the monolith. Meanwhile, the Sun rises slowly over the lip of the excavation, shining its light on the monolith for the first time in three million years.

In the film 2001, Floyd joins other bureaucrats for a group photo in front of the monolith. Set against the brooding monolith, which seems to soak up all light, this very human ritual is so mundane as to be comical. As the photographer gestures repeatedly for them to move closer together — a critical part of the group-photo ritual — the monolith interrupts by emitting a powerful electronic scream.

Floyd and the others stumble around in pain and confusion as their suit radios receive the signal and blast it into their helmets. Only later do they realize that, by exposing the monolith to the Sun, they have tripped an ancient alarm.

Sources

"2001: A Space Odyssey" Revisited — The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners," AIAA-97-2956, Stanley Borowski and Leonard Dudzinski; paper presented at the 33rd AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit in Seattle, Washington, 6-9 July 1997.

"2001: A Space Odyssey" Revisited — The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners, NASA/TM-1998-208830/REV2, Stanley Borowski and Leonard Dudzinski, NASA Glenn Research Center, June 2003.

Kubrick, Stanley, and Arthur C. Clarke, 2001: A Space Odyssey, directed by Stanley Kubrick, Metro Goldwyn Mayer, April 1968.

2001: A Space Odyssey, Screenplay by Stanley Kubrick and Arthur C. Clarke, pp. b35-b36a, 12/1965.

2001: A Space Odyssey, Arthur C. Clarke, New York: New American Library, October 1999.

The Making of Stanley Kubrick's 2001: A Space Odyssey, Piers Bizony, Taschen, 2014, p. 58-59.

2001Italia.it: A Blog Devoted to 2001: A Space Odyssey (http://www.2001italia.it/ — accessed 12 June 2016).

More Information

Could the Space Voyages in the Film and Novel "2001: A Space Odyssey" Really Happen? (Part 2)

Could the Space Voyages in the Film and Novel "2001: A Space Odyssey" Really Happen? (Part 3)

The Last Days of the Nuclear Shuttle (1971)

Think Big: A 1970 Flight Schedule for NASA's 1969 Integrated Program Plan

What If Galileo Had Fallen to Earth? (1988)

Galileo awaits its chance to fly. Image credit: NASA.

The U.S. Congress authorized new-start funding for the Jupiter Orbiter and Probe (JOP) on 19 July 1977, early in the Administration of President Jimmy Carter. When JOP development began officially on 1 October 1977, at the start of Fiscal Year 1978, NASA planned to launch the new robot explorer in January 1982 on STS-23, the 23rd operational flight of the Space Transportation System (STS). At the time, NASA still maintained the hopeful fiction that the STS could begin a series of six Orbital Test Flights in early 1979 and become operational in May 1980. Until 1986, the STS — the centerpiece of which was the Space Shuttle — was intended to replace all other U.S. launch vehicles.

At liftoff, the Shuttle stack comprised twin reusable Solid Rocket Boosters (SRBs), a reusable piloted Orbiter with a 15-by-60-foot payload bay and three Space Shuttle Main Engines (SSMEs), and an expendable External Tank (ET) containing liquid hydrogen and liquid oxygen propellants for the SSMEs. The STS also included upper stages for boosting spacecraft carried in the Orbiter payload bay to places beyond its maximum orbital altitude. Until the mid-1980s, many in NASA hoped that a reusable Space Tug — perhaps incorporating a propellant-saving aerobrake — would eventually replace the expendable upper stages.

At the start of STS-23 (and, indeed, at the beginning of all STS missions), the three SSMEs mounted on the aft end of Orbiter fuselage and the twin SRBs bolted to the side of the ET would ignite in sequence to push the Shuttle stack off the launch pad. SRB separation would then take place 128 seconds after liftoff at an altitude of about 155,900 feet and a speed of about 4417 feet per second.

The three SSMEs would operate until 510 seconds after liftoff, by which time the Orbiter and its ET would be moving at about 24,310 feet per second at an altitude of 362,600 feet above the Earth. The SSMEs would then shut down and the ET would separate, tumble, and break up as it fell back into dense atmospheric layers over the Indian Ocean.

The Orbiter, meanwhile, would ignite its twin Orbital Maneuvering System (OMS) engines at apogee (the high point in its Earth-centered orbit) to raise its perigee (the low point in its orbit) above 99.99% the Earth's atmosphere. By the time it completed its OMS maneuvers, the STS-23 Shuttle Orbiter would circle the Earth in a 150-nautical-mile-high low-Earth orbit (LEO).

The STS-23 crew would next open the Orbiter payload bay doors and release JOP and its three-stage solid-propellant Interim Upper Stage (IUS). After they maneuvered the Orbiter a safe distance away, the IUS first-stage motor would ignite to begin JOP's two-year direct voyage to Jupiter.

Early days: artist concept of Jupiter Orbiter and Probe. Image credit: NASA.

In February 1978, NASA gave JOP the name Galileo. Largely because of its reliance on the STS, Galileo suffered a series of costly delays, redesigns, and Earth-Jupiter trajectory changes. The first of these was, however, not the fault of the STS. As Galileo's design firmed up, it put on weight, and was soon too heavy for the three-stage IUS to launch directly to Jupiter.

In January 1980, NASA decided to split Galileo into two spacecraft. The first, the Jupiter Orbiter, would leave Earth in February 1984. The second, an interplanetary bus carrying Galileo's Jupiter atmosphere probe, would launch the following month. They would each depart LEO on a three-stage IUS and arrive at Jupiter in late 1986 and early 1987, respectively.

In late 1980, under pressure from Congress, NASA opted to launch the Galileo Orbiter and Probe out of LEO together on a liquid hydrogen/liquid oxygen-fueled Centaur G' upper stage. Centaur, a mainstay of robotic lunar and planetary programs since the 1960s, was expected to provide 50% more thrust than the three-stage IUS. Modifying it so that it could fly safely in the Shuttle Orbiter payload bay would, however, delay Galileo's Earth departure until April 1985. The spacecraft would arrive at Jupiter in 1987.

Another delay resulted when David Stockman, director of President Ronald Reagan's Office of Management and Budget, put Galileo on his "hit list" of Federal government projects to be scrapped in Fiscal Year 1982. The planetary science community campaigned successfully to save Galileo, but NASA lost the Centaur G' and three-stage IUS.

In January 1982, NASA announced that Galileo would depart Earth orbit in April 1985 on a two-stage IUS with a solid-propellant kick stage. The spacecraft would then circle the Sun and fly past Earth for a gravity-assist that would place it on course for Jupiter. The new plan would add three years to Galileo’s flight time, postponing its arrival at Jupiter until 1990.

In July 1982, Congress overruled the Reagan White House when it mandated that NASA launch Galileo from LEO on a Centaur G'. The move would postpone its launch to 20 May 1986; however, because the Centaur could boost Galileo directly to Jupiter, it would reach its goal in 1988, not 1990. NASA designated the STS mission meant to launch Galileo STS-61G.

Artist concept of Galileo on a Centaur G' stage. Image credit: NASA.

There matters rested until 28 January 1986, when, 73 seconds into mission STS-51L, the Orbiter Challenger was destroyed. A joint between two of the cylindrical segments making up the Shuttle stack's right SRB leaked hot gases that rapidly eroded O-ring seals. A torch-like plume formed and impinged on the ET and the lower strut linking the ET to the SRB. The plume breached and weakened the ET's liquid hydrogen tank, causing the strut to separate. Still firing — the SRBs were not designed to be turned off once ignited — the right SRB pivoted on its upper attachment and crushed the ET's liquid oxygen tank. Hydrogen and oxygen mixed and ignited in a giant fireball.

Despite appearances, Challenger did not explode. Instead, the Orbiter began a tumble while moving at about twice the speed of sound in a relatively dense part of Earth's atmosphere. This subjected it to severe aerodynamic loads, causing it to break into several large pieces. The pieces, which included the crew compartment and the tail section with its three SSMEs, emerged from the fireball more or less intact. The mission's main payload, the TDRS-B data relay satellite, remained attached to its two-stage IUS as Challenger's payload bay disintegrated around it.

The pieces arced upward for a time, reaching a maximum altitude of about 50,000 feet, then fell, tumbling, to crash into the Atlantic Ocean within view of the Shuttle launch pads at Kennedy Space Center, Florida. The crew compartment impacted 165 seconds after Challenger broke apart and sank in water about 100 feet deep.

NASA grounded the STS for 32 months. During that period, it put in place new flight rules, abandoned potentially hazardous systems and missions, and, where possible, modified STS systems to help improve crew safety. On 19 June 1986, NASA canceled the Shuttle-launched Centaur G' for reasons of safety. On 26 November 1986, it announced that a two-stage IUS would launch Galileo out of LEO. The Jupiter spacecraft would then perform gravity-assist flybys of Venus and Earth. On 15 March 1988, NASA scheduled Galileo's launch for October 1989, with arrival at Jupiter to follow in December 1995.

One month after NASA unveiled Galileo's newest flight plan, Angus McRonald, an engineer at the Jet Propulsion Laboratory (JPL) in Pasadena, California, completed a brief report on the possible effects on Galileo and its IUS of a Shuttle accident during the 382-second period between SRB separation and SSME cutoff.

McRonald was not specific about the nature of the "fault" that would produce such an accident, though he assumed that the Shuttle Orbiter would become separated from the ET and would tumble out of control. He based his analysis on data provided by NASA Johnson Space Center in Houston, Texas, where the Space Shuttle Program was managed.

The Space Shuttle was by far the largest spacecraft to launch with astronauts on board. It was immensely capable — but with capacity came complexity, making it vulnerable. Image credit: NASA.

McRonald also examined the effects of aerodynamic heating on Galileo's twin electricity-generating Radioisotope Thermoelectric Generators (RTGs). The RTGs would each carry 18 General Purpose Heat Source (GPHS) modules containing four iridium-clad plutonium dioxide pellets each. The GPHS modules were encased in graphite and housed in protective aeroshells, making them unlikely to melt following an accident during Shuttle ascent. In all, Galileo would carry 34.4 pounds of plutonium.

McRonald assumed that both the Shuttle Orbiter and the Galileo/IUS combination would break up when subjected to atmospheric drag deceleration equal to 3.5 times the pull of gravity at Earth's surface. Based on this, he determined that the Orbiter and its Galileo/IUS payload would always break up if a fault leading to "loss of control" occurred after SRB separation.

The Shuttle Orbiter would not break up immediately after loss of control occurred, however. At SRB separation altitude, atmospheric density would be low enough that the spacecraft would be subjected to only about 1% of the drag that tore apart Challenger. McRonald determined that the Shuttle Orbiter would ascend unpowered and tumbling, attain a maximum altitude, and fall back into the atmosphere, where drag would rip it apart.

He calculated that, for a fault that occurred 128 seconds after liftoff — that is, at the time the SRBs separated — the Shuttle Orbiter would break up as it fell back to 101,000 feet of altitude. The Galileo/IUS combination would fall free of the disintegrating Orbiter and break up at 90,000 feet, then the RTGs would fall to Earth without melting. Impact would take place in the Atlantic about 150 miles off the Florida coast.

For an intermediate case — for example, if a fault leading to loss of control occurred 260 seconds after launch at 323,800 feet of altitude and a speed of 7957 feet per second — then the Shuttle Orbiter would break up when it fell back to 123,000 feet. Galileo and its IUS would break up at 116,000 feet, and the RTG cases would melt and release the GPHS modules between 84,000 and 62,000 feet. Impact would occur in the Atlantic about 400 miles from Florida.

A fault that took place within 100 seconds of planned SSME cutoff — for example, one that caused loss of control 420 seconds after launch at 353,700 feet of altitude and at a speed of 20,100 feet per second — would result in an impact far downrange because the Shuttle Orbiter would be accelerating almost parallel to Earth's surface when it occurred. McRonald calculated that Orbiter breakup would take place at 165,000 feet and the Galileo/IUS combination would break up at 155,000 feet.

McRonald found (somewhat surprisingly) that, in such a case, Galileo's RTG cases might already have melted and released their GPHS modules by the time the Jupiter spacecraft and its IUS disintegrated. He estimated that the RTGs would melt between 160,000 and 151,000 feet about the Earth. Impact would occur about 1500 miles from Kennedy Space Center in the Atlantic west of Africa.

Impact points for accidents between 460 seconds and SSME cutoff at 510 seconds would be difficult to predict, McRonald noted. He estimated, however, that loss of control 510 seconds after liftoff would lead to wreckage falling in Africa, about 4600 miles downrange.

McRonald summed up his findings by writing that Galileo's RTG cases would always reach Earth's surface intact if an accident leading to loss of control occurred between 128 and 155 seconds after liftoff. If the accident occurred between 155 and 210 seconds after launch, then Galileo's RTG cases "probably" would not melt. If it occurred 210 seconds after launch or later, then the RTG cases would always melt and release the GPHS modules.

STS flights resumed in September 1988 with the launch of the Orbiter Discovery on mission STS-26. A little more than a year later (18 October 1989), the Shuttle Orbiter Atlantis roared into space at the start of STS-34. A few hours after liftoff, the Galileo/two-stage IUS combination was raised out of the payload bay on an IUS tilt table and released. The IUS first stage ignited a short time later to propel Galileo toward Venus.

Free at last: Galileo and its two-stage IUS shortly after release from the Space Shuttle Orbiter Atlantis, October 1989. Image credit: NASA.

Galileo passed Venus on 10 February 1990, adding nearly 13,000 miles per hour to its speed. It then flew past Earth on 8 December 1990, gaining enough speed to enter the Main Belt of asteroids between Mars and Jupiter, where it encountered the asteroid Gaspra on 29 October 1991.

Galileo's second Earth flyby on 8 December 1992 placed it on course for Jupiter. The spacecraft flew past the Main Belt asteroid Ida on 28 August 1993 and had a front-row seat for the Comet Shoemaker-Levy 9 Jupiter impacts in July 1994.

Flight controllers commanded Galileo to release its Jupiter atmosphere probe on 13 July 1995. The spacecraft relayed data from the probe as it plunged into Jupiter’s atmosphere on 7 December 1995. Galileo fired its main engine the next day to slow down so that the giant planet's gravity could capture it into orbit.

Artist concept of Galileo in communication with its Jupiter atmosphere probe. Blue dots linking the low-gain antenna and Jupiter represent radio signals. After the spacecraft's large main antenna jammed partly open (left), the low-gain antenna, much less powerful, became Galileo's link with Earth. Image credit: NASA.

Galileo spent the next eight years touring the Jupiter system. It performed gravity-assist flybys of the four largest Jovian moons to change its Jupiter-centered orbit. Despite difficulties with its umbrella-like main antenna and its tape recorder, it returned invaluable data on Jupiter, its enormous magnetosphere, and its varied and fascinating family of moons over the course of 35 orbits about the giant planet.

As Galileo neared the end of its propellant supply, NASA decided to dispose of it to prevent it from accidentally crashing on and possibly contaminating Europa, the ice-crusted, tidally warmed ocean moon judged by many to be of high biological potential. On 21 September 2003, the venerable spacecraft dove into Jupiter's turbulent, banded atmosphere and disintegrated.

Sources

Galileo: Uncontrolled STS Orbiter Reentry, JPL D-4896, Angus D. McRonald, Jet Propulsion Laboratory, 15 April 1988.

Mission to Jupiter: A History of the Galileo Project, NASA SP-2007-4231, Michael Meltzer, NASA History Division, 2007.

More Information

A 1974 Plan for a Slow Flyby of Comet Encke

What Shuttle Should Have Been: NASA's October 1977 Space Shuttle Flight Manifest

Where to Launch and Land the Space Shuttle? (1971-1972)

The 1991 Plan to Turn Space Shuttle Columbia Into a Low-Cost Space Station

This NASA artwork from 1972 portrays the sheer volume of the Skylab Orbital Workshop, the first U.S. space station.

The first U.S. space station was Skylab, which NASA carefully dubbed an "Orbital Workshop" in order to distinguish it from the "real" space station it hoped to launch into low-Earth orbit by the mid-1970s. Skylab — a converted Saturn S-IVB rocket stage with a pressurized volume of more than 12,500 cubic feet — was launched on the last Saturn V heavy-lift rocket to fly. Three three-man crews lived and worked on board the 22-foot-diameter single-launch station for a total of 171 days between 26 May 1973 and 8 February 1974.

Nearly three years earlier, budget cuts had halted Saturn V production, so NASA had been forced to abandon plans for a single-launch, 33-foot-diameter core station. The Space Shuttle, originally intended as a cost-saving fully reusable space station crew and cargo transport, was subsequently tapped to serve also as the sole launch vehicle for a multi-modular space station built up over the course of many flights. This meant that the Shuttle Orbiter payload bay dimensions (15 feet in diameter by 60 feet long) and maximum payload mass (in theory, up to 32.5 tons) would dictate the size and mass of station modules and other components.

NASA's single-launch core station (left) would throughout its life receive independently maneuverable add-on modules delivered by fully reusable Shuttle Orbiters. This 1970 illustration depicts one such module outfitted to transport astronauts and cargo from the Shuttle payload bay to the core station main docking port and back. The modules would also be outfitted as special-purpose labs that would link up with round ports scattered over the station's hull. Image credit: McDonnell Douglas.

Launching the space station in the Shuttle payload bay meant also that NASA could not begin to assemble it until after Space Shuttle development and flight testing were completed. When the last crew left Skylab, the Shuttle's orbital maiden flight was officially set for early 1978. Operational flights were to start by 1980. Some hoped that an early Shuttle flight might boost Skylab to a higher orbit, postponing its eventual reentry and perhaps permitting it to be outfitted as a temporary interim space station in the early 1980s.

In the event, the first mission of the partially reusable Shuttle, STS-1, did not lift off until 12 April 1981, nearly two years after Skylab reentered and broke up over Australia (11 July 1979). The Orbiter Columbia remained aloft for two days before gliding to a landing on the dry lake-bed at Edwards Air Force Base (EAFB), California.

By then, engineers at NASA's Johnson Space Center had been at work for more than two years on a design for a Shuttle-launched station they dubbed the Space Operations Center (SOC). The SOC included a laboratory for experiments in microgravity, but was conceived mainly as a construction site for large structures, a servicing center for satellites, and a home port for a small fleet of space tugs. It was intended, in fact, to serve as a space shipyard, where would be assembled spacecraft for voyages beyond low-Earth orbit and large space structures such as Solar Power Satellites.

The 1982 Space Operations Center design became the point of departure for NASA station studies after the creation of the Space Station Task Force. Visible is a skeletal "false Shuttle payload bay" for satellite servicing and a hexagonal space tug hangar. Image credit: NASA.

On 20 May 1982, a little more than a year after STS-1 and a little more than a month before STS-4 (27 June-4 July 1982), NASA Administrator James Beggs established the NASA-wide Space Station Task Force. President Ronald Reagan was on hand at EAFB Runway 22 that U.S. Independence Day to welcome home the STS-4 crew. Some within NASA hoped that he would use the occasion to declare his support for a permanent Earth-orbiting space station, "the next logical step" after the Shuttle. Instead, Reagan declared that STS-4 was the final Shuttle test flight. With its next flight, STS-5, the Space Shuttle would be considered operational.

Reagan withheld his support for a further 18 months, until the beginning of the 1984 election year, when endorsing a space station — which was bound to create thousands of jobs — could provide maximum political advantage. During his 25 January 1984 State of the Union Address, he echoed President John F. Kennedy's May 1961 "Urgent National Needs" speech by calling on the U.S. civilian space agency "to develop a permanently manned space station and to do it within a decade." Reagan made mention only of the station's role as a laboratory. The station would, he said, "permit quantum leaps in our research in science, communications and in metals and life-saving medicines that can only be manufactured in space."

The Reagan White House disdained a space shipyard for two reasons. First, it was a relatively complicated design that could not be built for $8 billion spent over 10 years, the maximum price Administration budget watchdogs were willing to pay for a space station. The second reason was related to the first: a shipyard in space implied that things would be built there, and that in turn implied a commitment to new expenditures in the future.

Despite this clear message, NASA did not abandon its plans for a shipyard in orbit. In August 1984, the space agency released a "reference configuration" intended to guide aerospace companies bidding on Space Station Program contracts. Called the "Power Tower," it included a 400-foot-long single main truss where SOC-type space construction equipment might eventually be mounted. In NASA artwork depicting the station, featureless boxes stood in for unspecified large user payloads and hoped-for shipyard elements.

The August 1984 Power Tower station configuration was the Space Operations Center with trusses added. The small spacecraft with twin solar arrays at upper right is a self-propelled free-flyer bearing experiments likely to be interfered with by other station activities (for example, astronaut movement). Image credit: NASA.

NASA envisioned that spacewalking astronauts would bolt together the Power Tower truss in orbit piece by piece. During Shuttle mission STS-61B (26 November-3 December 1985), in fact, spacewalkers successfully tested two truss-assembly methods in the payload bay of the Orbiter Atlantis.

From the Power Tower evolved the "Dual Keel" in late 1985. In May 1986, NASA released its Space Station "Baseline Configuration," a Dual-Keel station measuring 503 feet wide and 361 feet tall. The new design included about twice as many truss elements as the Power Tower, providing ample room for both space-facing and Earth-facing user payloads and eventual addition of space construction facilities. Assembly in orbit was to begin in 1992 and to be completed by Reagan's 1994 deadline.

The Baseline Configuration was dead on arrival, however, because of the 28 January 1986 loss of the Shuttle Orbiter Challenger and its seven-member crew. By March 1986, NASA and its contractors had begun to scale back the station. At first it shrank but retained its Dual-Keel shape. After that, in the "revised baseline configuration" of 1987, it lost its keel trusses, becoming only a single truss with solar arrays at either end and laboratory and habitat modules at its center. NASA made sure, however, that the design included "hooks" and "scars" that would enable eventual expansion to the Dual-Keel design.

NASA's ambitious Dual-Keel Baseline Configuration of May 1986 was dead on arrival. Image credit: NASA.

President Reagan christened the Space Station Freedom in 1988; a gesture which for some rang hollow (they had hoped he might support a moon and Mars program that would give Freedom a long-term direction). The following year, with the Station expected to be over-budget, overweight, under-powered, and too demanding to build, NASA entirely abandoned the Dual Keel configuration. At the same time, planners proposed that NASA make plans to build an advanced "transportation node" space station in the early 21st century. This proposed separation of functions was an acknowledgment that the jolts and vibrations one could expect on board an orbital shipyard would wreak havoc with microgravity laboratory experiments.

The year 1990 saw new problems. Persistent hydrogen fuel leaks grounded the three-orbiter Shuttle fleet for nearly half the year, renewing doubts about the Shuttle's ability to reliably launch, assemble, resupply, and staff Freedom. Against this background, news emerged of a dispute within NASA over estimates of the number of spacewalks required to build and maintain the Space Station. The row triggered congressional hearings in May 1990.

In a report released on 20 July 1990, former astronaut and spacewalker William Fisher and JSC robotics engineer Charles Price, co-chairs of the Space Station Freedom External Maintenance Task Team, declared that Freedom would need four two-man spacewalks per week during its assembly and 6,000 hours of maintenance spacewalks per year after its completion. This amounted to 75% more spacewalks than the official NASA estimate, which was already considered excessive. Fisher called the spacewalk requirement "the greatest challenge facing the Space Station."

In November 1990, with new budget cuts in the offing, NASA began yet another Freedom redesign. At about the same time, Space Industries Incorporated (SII), a small engineering firm for which Maxime Faget, co-designer of the Mercury capsule, worked as Technical Advisor, began to examine a radical new approach to solving Freedom's persistent problems. SII performed its Orbiter-Derived Station (ODS) study on contract to Rockwell International, prime contractor for the Shuttle Orbiter.

SII noted that the U.S. House of Representatives Committee on Science, Space, and Technology wanted a "permanently manned Space Station, that meets our International Agreements, retains a capability for evolution, and has minimum annual and aggregate cost." At the same time, it explained, scientists and engineers of the space technology development and microgravity and life sciences research communities wanted NASA to provide an orbiting laboratory "without spending the entire available budget on the laboratory rather than on the experiments."

To satisfy these needs, SII proposed to draw upon Space Shuttle design heritage and operational experience. Specifically, the company proposed that NASA launch in 1996 an unmanned "stripped-down" Orbiter — one without wings, tail, landing gear, body flap, forward reaction control thrusters, and reentry thermal protection — to serve as Freedom's largest single element.

Orbiter Derived Station in Man Tended Configuration after Mission Build-1. Image credit: SII/NASA.

Removing systems with a total mass of 45,600 pounds would boost the Orbiter's payload capacity to 81,930 pounds, permitting it to transport a 56.5-foot-long pressurized module permanently mounted in its payload bay and four pairs of rolled-up 120-foot-long solar arrays under streamlined housings along its sides. The pressurized module would include a single docking port on top and a short tunnel linking it to the stripped-down Orbiter's two-deck crew compartment. In effect, SII's ODS launch approach would briefly restore the heavy-lift capability lost when the U.S. abandoned the Saturn V rocket.

What follows is a synthesis of information from two SII documents concerning the ODS. The first, a set of presentation slides, is not dated, though individual slides in the presentation carry July 1991 dates. The second document is SII's final report to Rockwell International dated September 1991. When the documents differ in significant ways, this is noted.

Copying NASA parlance, SII referred to the launch of the stripped-down Orbiter as Mission Build-1 (MB-1). Upon achieving a 220-nautical-mile-high orbit inclined 28.5° relative to Earth's equator, the ODS would turn its payload bay doors toward Earth, open them to expose the pressurized module and door-mounted radiators, and unroll its solar arrays to generate up to 120 kilowatts of electricity. At that point, the ODS would achieve Man-Tended Configuration (MTC). MTC meant that the station could be staffed while a Shuttle Orbiter was docked with it. According to SII, NASA's Freedom would not achieve MTC until MB-6, and its solar arrays would not generate 120 kilowatts of electrical power until MB-10.

Orbiter Derived Station (top) and Shuttle Orbital Maneuvering System propulsion pod design differences. Image credit: SII/NASA.

During a normal Space Shuttle mission, the twin 6,000-pound-thrust Orbital Maneuvering System (OMS) engines would ignite twice to complete orbital insertion after the Orbiter's three Space Shuttle Main Engines (SSMEs) shut down and and its External Tank separated. The OMS-1 burn would put the Orbiter into an elliptical orbit; then, at apogee (the high point of its orbit about the Earth), the OMS-2 burn would raise its perigee (the low point in its Earth orbit) to make its orbit circular. Subsequently, the OMS engines would be used to perform major maneuvers and would slow the Orbiter at the end of its mission so that it would reenter the atmosphere. The OMS engines would burn hypergolic (ignite-on-contact) hydrazine/nitric acid propellants.

SII proposed changes to the stripped-down Orbiter's OMS pods to increase reliability and enable long-duration use. A hydrazine monopropellant system would replace the baseline Orbiter bi-propellant system. The SSMEs would insert the stripped-down Orbiter directly into its initial elliptical orbit, then two sets of four 500-pound-thrust OMS engines — one set per OMS pod — would each draw on a pair of propellant tanks to perform the OMS-2 orbit-circularization burn at apogee. The roughly 13,000 pounds of propellant remaining after the OMS-2 burn would be sufficient to resist atmospheric drag and supply OMS pod attitude-control thrusters for two years.

SII suggested that the OMS tanks be refilled in orbit after they exhausted their initial load of hydrazine, but provided no details as to how this might be accomplished. Alternately, the company suggested, a new propulsion module might be docked with the ODS after the modified OMS pods ran out of propellant.

With MB-1 complete, SII's ODS would provide 11,000 cubic feet of pressurized volume containing 58 standardized payload racks. NASA’s Freedom, by comparison, would have no pressurized volume at all until the addition of the U.S. Lab during MB-6, and would not exceed 10,000 cubic feet of pressurized volume until MB-13. The U.S. Hab and Lab modules would together hold only 48 racks.

In SII's July 1991 ODS design, the large module launched in the stripped-down Orbiter payload bay on MB-1 included only Hab module functions, and MB-2 in 1997 would see a piloted Shuttle Orbiter deliver the U.S. Lab module. In its September 1991 final report, SII combined Lab and Hab in the stripped-down Orbiter payload bay and substituted a 47.5-foot-long "core module" for the Lab on MB-2. The cylindrical core would include eight docking ports on its sides and one at either end.

One of the core module end ports would be docked permanently with the port on the Hab/Lab module. Visiting Shuttle Orbiters would dock with the Earth-facing port at the core module's other end. Addition of the core module would increase ODS pressurized volume to 15,000 cubic feet. NASA's Freedom station would not exceed 15,000 cubic feet of volume until MB-16.

SII envisioned that ODS assembly flights would be interspersed with utilization flights beginning immediately after MB-1. The first ODS utilization mission would occur in 1996, and three would take place in 1997.

In addition to permitting early research on board the ODS, some utilization flights after MB-2 would deliver supplies and equipment in a drum-shaped Logistics/Life Support Module (LLSM). Astronauts would dock the LLSM to a core module side port using the visiting Orbiter's Canada-built Remote Manipulator System (RMS). Spent LLSMs would be returned to Earth for refurbishment and reuse. SII placed the ODS toilet and shower in the LLSM, arguing that servicing waste and water systems on the ground would be preferable to doing so in orbit.

SII noted that its Station would need very few assembly and maintenance spacewalks. It would, nevertheless, include a modified Shuttle Orbiter airlock attached to one of its core module side ports. The airlock would reach the ODS during an unspecified utilization flight after MB-2. Because ODS assembly would be relatively simple and assembly spacewalks minimal, SII assumed that the Station could do without its own Canada-built RMS. The company did not address how deletion of the Station RMS would affect U.S.-Canada relations.

The second assembly mission of 1997, MB-3, would see arrival of an Orbiter bearing in its payload bay an eight-man Assured Crew Return Vehicle (ACRV), a space station lifeboat. With the docking of the ACRV at a core module side port, the ODS could be staffed by eight astronauts with no Orbiter present. NASA called the ability to maintain a full crew with no Orbiter present "Permanent Manned Configuration" (PMC). NASA's Freedom Station would not achieve PMC until MB-16.

Orbiter Derived Station in Assembly Complete configuration after Mission Build-6 in late 1998. The image displays an RMS robot arm, though SII stated that the stripped-down Orbiter would not carry one. Image credit: SII/NASA.

The year 1998 would see three assembly flights, all international in character. In his January 1984 State of the Union speech, Reagan had invited U.S. allies to lend a hand in building NASA's space station in exchange for opportunities to reap its rewards. In addition to Canada, Japan and Europe had answered the call.

MB-4 would see an Orbiter deliver the pressurized part of the Japanese Experiment Module (JEM). Astronauts would use the Orbiter's RMS to dock it to a core module side port. During MB-5, astronauts would use the visiting Orbiter RMS to add the European Space Agency's Columbus laboratory module. With that, the SII's ODS would achieve its maximum pressurized volume: 24,000 cubic feet, or about 8,000 cubic feet more than planned for NASA's Freedom Station. MB-6 would add Logistics and unpressurized Exposure components to complete the JEM.

SII recommended that the core module's Earth-facing port be designed to rotate so that visiting Orbiters could optimally position themselves for assembly missions. During MB-5, for example, the visiting Orbiter's nose would face in the ODS's direction of flight so that its RMS could place the Columbus module at its designated core module side port. During MB-4 and MB-6, it would face in the opposite direction so that JEM components could be added.

MB-6, which would take place near the end of 1998, would mark the end of ODS assembly. By then, SII's station would have hosted seven utilization flights. For comparison, NASA's Freedom Space Station would host no utilization flights until 1998, when three would take place. Freedom would not reach "Assembly Complete" until 2000.

SII proposed ways that the baseline ODS might be upgraded. The company noted that, beginning with MB-10, NASA's Freedom would provide experimenters with more electricity (180 kilowatts) than would the ODS. If this power level were judged to be necessary for ODS operations, then a 60-kilowatt "power kit" could be added during a utilization flight. The company suggested that the kit's rolled solar arrays be attached to a special port installed in the stripped-down Orbiter's nose behind a streamlined faring.

The ODS included no provision for space-facing experiments; all of its modules were expected to be mounted on its Earth-facing payload bay side. This reflected the science and technology community's desire for a microgravity lab and the fact that highly capable automated space-facing satellites (for example, the Hubble Space Telescope) were available. If, however, space-facing experiments were desired on board the ODS, then it could be launched with a docking port on the Orbiter's space-facing belly. A tunnel through the ODS payload bay floor would link the port to the Hab/Lab module.

Probably the company's most controversial proposal was to accelerate ODS assembly by stripping down Columbia, NASA's oldest Orbiter. SII noted that Columbia was the heaviest Orbiter, so had the least payload capacity. It assumed that NASA would want to replace Columbia with a new, less heavy Orbiter, thus increasing the Shuttle fleet's overall lift capacity. SII called this "disposing of the worst and and replacing it with the best." Some components stripped from Columbia could, it suggested, be reused in the new Orbiter to save money.

By the time SII submitted its final report, NASA's latest Freedom configuration had been public for three months. The new design included truss segments launched pre-assembled, smaller U.S. modules, and other changes meant to reduce the number of spacewalks and assembly flights required to build and maintain it. The station would, however, lose yet more capability (notably in the area of electrical power, which was reduced to about 60 kilowatts at PMC). The April 1991 redesign set the stage for Freedom's near-cancellation in June 1993 (it survived by a single vote in the U.S. House of Representatives) and, beginning later that year, its revival as the International Space Station.

This rendition of Space Station Freedom in its 1991 configuration contains several interesting features. The overall station design is obscured by shadows, denoting the uncertainty surrounding the station's future form. Only the international pressurized modules — the JEM and Columbus labs — are visible. Beginning with the the May 1986 Dual Keel, these modules changed very little in NASA artwork because the International Partners insisted that the U.S. adhere to its agreements. The U.S. modules, in the meantime, decreased in number and shrank to a fraction of their planned former size. A Shuttle Orbiter is displayed, but not attached to Freedom; placing it too close to the station would show plainly the 1991 station's small size relative to earlier designs. The moon and Mars are visible above Freedom; in 1991, NASA still paid lip-service to carrying out President George H. W. Bush's abortive Space Exploration Initiative (SEI), which aimed to launch humans to those worlds. Freedom was meant to play a role in furthering SEI's goals, though the precise nature of that role was not clear. Image credit: NASA.

Sources

The Space Shuttle at Work, NASA SP-432/EP-156, H. Allaway, NASA, 1979, pp. 64-72.

Aboard the Space Shuttle, NASA EP-169, F. Steinberg, NASA, 1980.

Space Station, NASA EP-211, D. Anderton, NASA, no date (1984).

Space Station: The Next Logical Step, NASA EP-213, W. Froehlich, NASA, no date (1985).

Space Station: Leadership for the Future, NASA PAM-509, F. Martin & T. Finn, NASA, August 1987.

Space Station: A Step Into the Future, NASA PAM-510, A. Stofan, NASA, November 1987.

Space Station Freedom Reference Guide, Boeing, 1988.

Space Station Freedom: A Foothold on the Future, NASA NP-107, L. David, NASA, October 1988.

"Freedom Spacewalks 'unacceptable': NASA," Flight International, 1-7 August 1990, p. 18.

"Freedom failure threatens NASA's future," T. Furniss, Flight International, 29 May-4 June 1991, p. 34.

"Operation Scale-Down," T. Furniss, Flight International, 29 May-4 June 1991, pp. 76-78.

Shuttle Derived Space Station Freedom, Space Industries International, Inc./Rockwell International Space Systems Division, presentation materials, n.d. (July 1991).

Expanded Orbiter Missions Final Report: Orbiter Derived Space Station Freedom Concept, prepared by Space Industries, Inc. (SII), Webster, Texas, for Rockwell International, Inc., Downey, California, September 1991.

"House Retains Space Station in a Close Vote," C. Krauss, International New York Times, 24 June 1993 (http://www.nytimes.com/1993/06/24/us/house-retains-space-station-in-a-close-vote.html - accessed 16 October 2015).

International Space Station, Boeing, May 1994.

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NASA's 1992 Plan to Land Soyuz Space Station Lifeboats in Australia

NASA's 1992 Plan to Land Soyuz Space Station Lifeboats in Australia

Image credit: NASA.

Kosmos 133, the first in the long line of Soyuz ("union") spacecraft, lifted off without a crew from Baikonur Cosmodrome in Central Asia on 28 November 1966. Its mission: to dock with Kosmos 134, another Soyuz without a crew scheduled for launch the following day. The Kosmos 133-Kosmos 134 combined mission was meant to put Soyuz through its paces ahead of a nearly identical piloted Soyuz docking mission.

The Soviet Union's new piloted spacecraft was a union of three modules, which together weighed about 7000 kilograms. They were, from aft to fore, the cylindrical Service Module; the 2900-kilogram Descent Module; and, linked to the Descent Module by a hatchway, the spherical Orbital Module.

The cramped Descent Module was the only part of Soyuz spacecraft meant to withstand reentry. In addition to a heat shield, parachutes, and solid-propellant rockets for soft-landing on land, it included the main control console and three cosmonaut launch and landing couches.

The Service Module carried a pair of solar array "wings" on its sides for making electricity. It included the main engine that enabled it to change its orbit; orbit-changing maneuvers included the deorbit burn performed when time came to return home. The Orbital Module provided extra living and storage space and carried a docking unit. Both the Orbital Module and the Service Module were cast off following the deorbit burn and to disintegrate high in the atmosphere.

Any joy flight controllers near Moscow felt as Kosmos 133 soared above the Earth vanished when they found that its attitude control system did not work properly. They called off the Kosmos 134 launch. Several times they tried to orient Kosmos 133 to point its main engine in its direction of orbital motion so that they could slow the spacecraft and begin reentry. On 30 November, they commanded the first Soyuz to self-destruct when it appeared that its Descent Module would land in China.

November 1966: Kosmos 133, the first Soyuz spacecraft, was launched without a crew. This widely used illustration, of unknown provenance, shows its three modules. From left to right they are: the Orbital Module; the Descent Module; and the Service Module.

When reporting on the half decade that followed Kosmos 133, it needs less space to describe Soyuz and Soyuz-derived spacecraft successes than it does to list their failures. Kosmos 186 and Kosmos 188 successfully performed the first automated docking in late October 1967, and Kosmos 212 and Kosmos 213 repeated the feat in April 1968.

In January 1969, the piloted Soyuz 4 and Soyuz 5 spacecraft docked and two cosmonauts space-walked between them. Zond 7, a prototype circumlunar Soyuz variant without an Orbital Module, flew without a crew around the moon and landed as planned in the Soviet Union in August 1969, a month after Apollo 11 became the first mission to land men on the Moon. The two-man crew of Soyuz 9 orbited Earth for nearly 18 days in June 1970, breaking the space endurance record Gemini VII had set in 1966.

These scattered successes should not obscure the fact that, of the 16 individual cosmonauts launched on Soyuz between 1967 and 1971, one-quarter lost their lives. Of the more than 30 Soyuz-derived spacecraft launched in the same period, all but nine failed in some significant way.

Following the deaths of the three Soyuz 11 cosmonauts after they undocked from the Salyut 1 space station on 29 June 1971, Soyuz underwent a major redesign. When piloted Soyuz flights resumed in September 1973, the spacecraft could carry no more than two space-suited cosmonauts. Soyuz spacecraft suffered more malfunctions in the 1970s, often failing to reach their Salyut space station targets, but no more cosmonauts died.

The advent in 1977 of the highly reliable Progress variant, an automated cargo ship for resupplying space stations, marked a break from the past for Soyuz. Malfunctions tailed off and, after a dramatic booster explosion on the launch pad on 26 September 1983, no Soyuz failed to reach its space station target. Even the booster explosion could be seen as a sign of design maturity; despite suffering launch-escape system damage, the Soyuz-T-10a spacecraft saved its two-man crew.

Technology upgrades produced first the Soyuz-T and then the Soyuz-TM, which could transport up to three space-suited cosmonauts. By the early 1990s, Soyuz had developed a reputation for sturdy reliability.

Forward view of Soyuz-TM spacecraft. Image credit: NASA.

Aft view of Soyuz-TM spacecraft. Image credit: NASA.

Even before the Soviet Union collapsed in 1991, officials with the Soviet aerospace enterprise NPO Energia began to peddle its wares, including Soyuz, at major international aerospace meetings. An implied subtext of these promotional efforts was that, if the West would not buy products from the financially strapped Soviet aerospace sector, then its engineers might sell their technical expertise to countries opposed to Western interests.

The threat — and promise — of Soviet space technology soon attracted the attention of the U.S. government. Spaceflight entered the geopolitical arena in a way it had not done since the early 1970s, when the 1975 Apollo-Soyuz Test Project became the poster child for President Richard Nixon's policy of detente.

In December 1991, Congress directed NASA to study the feasibility of using the Soyuz-TM as a low-cost "lifeboat" or "escape pod" for its planned Space Station Freedom. The concept of a space station lifeboat is an old one, dating back at least to the 1960s. NASA had acknowledged the need for such a vehicle soon after the January 1986 Challenger accident killed seven astronauts and grounded the Space Shuttle fleet for almost three years.

NASA foresaw three scenarios in which a Space Station lifeboat might save lives. First, a medical emergency on board Space Station Freedom might require the rapid evacuation of a sick or injured astronaut. Second, a disaster — for example, a fire — might render Freedom uninhabitable. Finally, another Shuttle accident might ground the Orbiter fleet, stranding a crew on board Freedom with no resupply.

A NASA-designed ACRV for eight astronauts shortly after touchdown. Image credit: NASA.

By early 1992, NASA had offered up several designs for an Assured Crew Return Vehicle (ACRV), as it called its planned Space Station Freedom lifeboat. Unfortunately, even the simplest design would cost at least $1 billion to develop. It would, after all, constitute a wholly new piloted spacecraft designed to remain docked to Freedom for years, dormant but always ready.

As part of the preliminary Soyuz ACRV feasibility study for Congress, NASA engineers traveled to Moscow in March 1992 to meet with Russian government and NPO Energia officials. The space agency completed its study the following month.

In its study report, NASA portrayed Soyuz-TM as an interim lifeboat for the period when Space Station Freedom's crew numbered no more than three astronauts. Use of Soyuz-TM would, it was hoped, bring nearer the day when Freedom could be staffed continuously. In about the year 2000, as Freedom's population grew to six or eight astronauts, an "optimized" U.S.-built ACRV would take over from Soyuz-TM.

June 1992: U.S. President George H. W. Bush (right) and Russian President Boris Yeltsin. Image credit: National Archives.

On 17 June 1992, U.S. President George H. W. Bush and Russian Federation President Boris Yeltsin signed agreements in Moscow providing for broad space cooperation. A Russian cosmonaut would fly on the Space Shuttle, a U.S. astronaut would live on board the Mir space station, and a Shuttle Orbiter would dock with Mir. The following day, NASA and the Russian Space Agency signed a $1-million contract to jointly assess Russian space technology, including Soyuz-TM, for use in NASA programs.

It had, of course, already become evident that Soyuz-TM would need modifications before it could serve as an ACRV for Freedom. Its Russian language control panel labels would, for example, need to be replaced with labels in English. More significantly, its on-orbit endurance would need to be stretched from 180 days to three years and its docking unit would need to be made compatible with Freedom's docking ports. In addition, NPO Energia would need to find a way to squeeze NASA's tallest astronauts into the cramped Soyuz Descent Module.

Even more challenging was Space Station Freedom's planned orbit about the Earth. NASA expected to assemble its station in an orbit inclined 28.5° relative to Earth's equator. It would orbit over an equator-centered, globe-girdling band of Earth's surface spanning from 28.5° north latitude to 28.5° south latitude. Freedom's planned inclination meant that a Shuttle Orbiter launched from Kennedy Space Center, located on Florida's east coast at 28.5° north latitude, would in theory be capable of reaching the station bearing its maximum possible payload.

Space Station Freedom's orbit meant that, if Soyuz-TM were launched from Baikonur Cosmodrome on the usual Soyuz launch vehicle, then it could not reach the U.S. station. The sprawling Central Asian launch site is located in Kazakhstan at 46° north. The Soyuz launcher normally propels Soyuz and Progress spacecraft toward an orbit inclined 51.6° relative to the equator to avoid flying over China during ascent. This meant that, upon reaching orbit, the Soyuz-TM ACRV would need to change its orbital plane by a whopping 23.1° to rendezvous with Freedom.

Each degree of plane change would demand hundreds of kilograms of propellants. If the Soyuz ACRV were launched to Space Station Freedom from Baikonur, then the larger, more powerful, and more costly four-stage Proton launcher would have to do the job. Its entire fourth stage, suitable for boosting spacecraft out of Earth orbit toward the Moon and planets, would be expended to accomplish the required plane change.

NASA envisioned that a Shuttle Orbiter launched from Kennedy Space Center would deliver the Soyuz ACRV to Space Station Freedom. Once there, Orbiter or Station robot arms would pluck the Soyuz ACRV from the Orbiter payload bay and berth it at a waiting Freedom docking port. Alternately, the Soyuz ACRV might be launched minus a crew from Florida on a U.S. expendable rocket such as Atlas and perform an automated rendezvous and docking with Freedom.

Space Station Freedom's 28.5° orbital inclination would limit where the Soyuz ACRV's Descent Module could land after it evacuated a crew. The normal Soyuz landing area is located at about 50° north, far beyond the range of a Soyuz ACRV returning from Freedom.

In a June 1993 report, the ACRV Project Office at NASA Johnson Space Center in Houston, Texas, summed up a study of potential Soyuz ACRV landing zones. It noted that, because of Space Station Freedom's orbital inclination, a Soyuz ACRV could land on U.S. soil only in south Texas and south Florida. (The report made no mention of Hawaii, the southernmost U.S. state, over which Freedom would pass regularly.)

The ACRV Project Office then looked abroad to friendly countries with wide-open spaces. Australia appeared ideal. The northern two-thirds of the country lies between 28.5° and 10° south latitude and much of its interior is flat, arid, and sparsely populated.

As part of the June 1992 contract activities, NASA engineers and officials, a U.S. State Department representative, and NPO Energia engineer Valentin Ovciannikov traveled to Australia in November 1992 to conduct a preliminary assessment of four candidate Soyuz ACRV landing zones. The Australian Space Office (ASO), working with the Australian Geological Survey Organization and the National Resource Information Center, chose the zones based on NPO Energia and NASA selection criteria.

November 1992: The NASA ACRV Project Office team's route through Australia during its tour of prospective Soyuz ACRV landing zones. Image credit: David S. F. Portree/NASA.

The landing zone survey team stopped first in Australia's capital, Canberra, to meet with government officials. NASA expected that Australia, a signatory of the 1967 United Nations "Agreement on the Rescue of Astronauts, the Return of Astronauts, and the Return of Objects Launched into Space," would stand ready to assist space travelers forced to land on its territory. The team found tentative support for its plans, though the Australians made it clear that they would approve nothing until the U.S. and Australia signed a nation-to-nation treaty covering responsibility for costs and damages.

On 11 November the team began a whirlwind eight-day, 9800-kilometer tour of the proposed landing zones. Team members flew first to Adelaide, the capital of South Australia. There they met with state police to describe the Soyuz ACRV mission and learn about Search and Rescue (SAR) capabilities in the Coober Pedy-Oodnadatta region. Coober-Pedy, "the Opal Capital of the World," is a town of about 2000 people in the Australian Outback north of Adelaide.

The team learned that the police were responsible for SAR operations throughout Australia, and that Australian SAR personnel and equipment were concentrated in capital cities, not scattered among small Outback communities. In South Australia, the state police had four elite rescue teams and three small airplanes that could reach Coober Pedy's 1400-meter-long asphalt runway in two and a half hours. They leased a single helicopter that could reach the area in four hours.

The next day (12 November), the team flew to Coober Pedy in a small chartered plane. There they learned that the local police and mine rescue service had at their disposal several four-wheel-drive vehicles and an ambulance. They found that much of the area was dry and flat with red, gravel-covered soil of good bearing strength. The hard surface would enable four-wheel-drive vehicles to reach points throughout the area and would help to ensure that the Soyuz ACRV land-landing system would operate properly.

As an aside, the team noted in its report that NASA could learn a great deal by participating in a Soyuz-TM landing. NASA engineers subsequently observed the Soyuz-TM 16 landing in Kazakhstan on 22 July 1993. 

It was an appropriate landing for them to observe, for the spacecraft had been used to test a Russian-built APAS-89 universal docking unit of the type U.S. Shuttle Orbiters would use to dock with the Mir station during Shuttle-Mir missions (1994-1998). The APAS-89 system, which was based on the U.S.-Soviet APAS-75 system developed jointly for ASTP, had been built originally to enable the Soviet Buran shuttle to dock with Mir and its planned successor, Mir-2.

In the south part of the Coober Pedy zone, the survey team gathered data on the "moon plain," a large area where trees — gidgee and acacia — grew along dry watercourses and the soil had "fair to poor" bearing strength. They also noted a field of small sand dunes. NPO Energia's Ovciannikov worried that the Soyuz ACRV Descent Module might roll between two dunes and become stuck with its top-mounted crew hatch buried in the sand. Using a hand-held anemometer and historical weather data from the Australian Bureau of Meteorology, the team determined that wind speeds near Coober Pedy would be acceptable for Soyuz ACRV landings.

The team spent the night in Coober Pedy listening to the distant howls and barks of dingoes, then flew on to Perth, the capital of Western Australia. On 13 November they discussed with state police the SAR capabilities in the area of Meekatharra, about 1240 kilometers to the northeast.

They also learned of the Royal Flying Doctor Service (RFDS), which had one of its 14 bases in Perth. RFDS provided rapid medical response to two-thirds of the Australian continent, including all four of the candidate Soyuz ACRV landing zones. In their report, the team suggested that NASA doctors should begin to coordinate with the RFDS as soon as possible.

The police in Perth made it clear that present-day local needs had priority over any future NASA needs. They asked to be alerted 24 hours before an expected Soyuz ACRV landing. In its report, the team noted that this would not be possible for a medical or emergency evacuation, though it would be possible for a crew returning from Freedom during a prolonged Shuttle stand-down.

The team flew to Meekatharra on 14 November. Of great interest was a 2180-meter-long, 45-meter-wide asphalt runway at the Meekatharra Airport. In their report, the team suggested that the runway, built originally for emergency Boeing 707 landings, might be used to land cargo planes bearing rescue equipment, four-wheel-drive vehicles, and helicopters.

The team judged that Meekatharra's soil had "excellent" bearing strength. Acacia and munga trees stood over less than 10% of the area, which was very flat. There were, however, scattered bedrock outcrops protruding from the windswept plain. In addition to presenting a minor impact hazard, the outcrops included naturally radioactive "uraniferous" deposits. Ovciannikov expressed concern that these might interfere with the Descent Module's altimeter, which relied on a radioactive source.

Meekatharra is only about 500 kilometers from Australia's west coast, a fact that had both pluses and minuses for Soyuz ACRV landings. On the one hand, it meant that debris from discarded Orbital Modules and Service Modules would not fall on land. On the other hand, the Descent Module might fall short of land if it followed a ballistic reentry path; that is, if it failed to rotate about its center of gravity to generate lift. Following a ballistic reentry, quick crew recovery might be crucial; a ballistic reentry would subject the astronauts, who might be weak after a long stay in weightlessness, to deceleration equal to 10 times Earth's surface gravity.

The team flew on to Darwin, capital of the Northern Territory, on 15 November. There territorial police described their 30-member Police Task Force, which was trained to deal with situations as diverse as riot control, bomb disposal, and cliff rescue.

The proposed Soyuz ACRV landing zone in the Northern Territory, the largest of the four candidates, was centered on the town of Tennant Creek (population 3200). The territorial police explained that their SAR resources were based both in Darwin, 970 kilometers from Tennant Creek, and in Alice Springs, 480 kilometers away.

The team visited the Tennant Creek zone on 16 November. They learned that the Tennant Creek police force included 25 officers but only one four-wheel drive vehicle. The police worried that the Soyuz ACRV soft-landing rockets might start brush fires. Ovciannikov assured them through an interpreter that they would not.

The team noted that the proposed landing zone was in the sprawling Barkley Tableland, a region of black-earth raised plains covered with gold-colored Mitchell grass. Ovciannikov observed that the area resembled the Soyuz-TM "landing grounds" around Dzhezkazgan, Kazakhstan.

Unlike the other landing zones, Tennant Creek had distinct wet and dry seasons, with the former occurring in the southern-hemisphere summer/early autumn months (December through March). Located just 19.5° south of the equator, it was also the hottest of the four zones, with an average of 22 days per year above 40° Celsius (104° Fahrenheit). Flooding from seasonal rains would not interfere with a Soyuz ACRV landing, Ovciannikov explained, though it might impede surface vehicles dispatched to recover the astronauts.

The team flew to Charleville in Queensland on 17 November without stopping in Brisbane, the state's capital. They found that the local airport included two asphalt runways, the largest of which was more than 1500 meters long and 30 meters wide. Though they met with local police, the team's report on the Charleville zone included no SAR data.

Charleville's rolling plains, or downs, differed from the other zones the team surveyed in that they included many large trees (briglow and sandalwood) interspersed with "square" and "circle" treeless areas used for grazing and farming. Charleville police told the team that local ranchers knocked down and burned the trees to create grazing land; if left alone, however, the trees grew back within a few years.

Ovciannikov compared Charleville to the "wooded steppe" on the north edge of the Soyuz-TM landing zone near Arkalyk, Kazakhstan. The open areas would make acceptable landing sites, he judged, though the bearing strength of the black and brown loamy soils could be rated only as "fair."

The team returned to Canberra late on 18 November. After another meeting with Australian government officials, during which they signed a document that summarized what the parties had learned and what had been agreed, its members departed Australia on 20 November 1992.

Soyuz-TM Descent Module on the treeless steppe in Kazakhstan. Image: NASA.

Shortly before the team began its Australian tour, U.S. voters went to the polls, where they favored Democrat William Clinton for President over Republican incumbent George H. W. Bush. Many in NASA feared that, after he took office in January 1993, Clinton would not support Space Station Freedom. With no station, their reasoning went, the Space Shuttle would lose its purpose, and U.S. piloted spaceflight would cease.

Clinton did not in fact support Space Station Freedom; that did not mean, however, that he failed to find value in a space station. On 9 March 1993, he ordered NASA to produce three low-cost station designs in 90 days. Aided by an advisory committee, he would then select one design for development.

The new President then handed off supervision of NASA to his Vice President, Al Gore. On 25 March, Gore appointed members to the Advisory Committee on the Redesign of the Space Station. MIT's Charles Vest became its chair.

That same month, in a letter to NASA Administrator Daniel Goldin, Russian Space Agency director Yuri Koptev and NPO Energia director Yuri Semenov proposed what would become the NASA station program's salvation: a merger of the financially strapped, politically troubled Freedom and Mir-2 programs. They proposed that the joint station be assembled in an orbit inclined more than 50° relative to Earth's equator. The following month, the Russians provided NASA with a straw-man assembly sequence for the joint station.

On 11 May 1993, Vest advised the White House that, regardless of the design selected, the U.S. station should be built in what he called a "world orbit" inclined between 45.6° and 51.6° so that Russian — and Chinese and Japanese — rockets could easily reach it. This would, he explained, ensure that redundant means of reaching and returning from the station would exist. He added that "the shuttle will likely be grounded during the operational life of the station."

Vest presented the Advisory Committee's report to the Clinton White House on 10 June 1993. Barely two weeks later, on 23 June 1993, the U.S. station program had a near-death experience: the U.S. House of Representatives approved Fiscal Year 1994 station funding by a margin of a single vote (215-216). The close vote, which showed how politically vulnerable Space Station Freedom had become, clearly conveyed to many in NASA that station program reform was essential.

President Clinton soon approved Option A, or Alpha, the redesign option most like Space Station Freedom. Meanwhile, the proposal to merge the U.S. and Russian station programs gained momentum. Engineers and managers in Moscow, Washington, and Houston began to refer to "Ralpha," which was short for "Russian Alpha."

On 2 September 1993, Vice President Gore and Russian Prime Minister Viktor Chernomyrdin released a joint statement on U.S.-Russian space cooperation. In it, they announced a dramatic expansion of the space cooperation outlined in the June 1992 Bush-Yeltsin agreement. Russia became a full partner in the space station; minus Russian participation, it simply would not fly.

At the same time, however, NASA would pay Russia for its involvement, which put the Russian Space Agency (and through it, NPO Energia) in the role of a NASA contractor. Though ambiguous and controversial in some quarters, the expanded Russian role reinforced the station's geopolitical justification, helping to ensure that the U.S. Congress would support it.

In November 1993, NASA and the Russian Space Agency completed an addendum to NASA's August 1993 Alpha Station Program Plan. It amounted to a blueprint for merging the Alpha and Mir-2 programs. The resulting International Space Station would be assembled in a 51.6° orbit, which meant that Soyuz spacecraft returning from it could land in their long-established recovery zones in central Asia.

Sources

Mir Hardware Heritage, NASA RP-1357, David S. F. Portree, NASA Lyndon B. Johnson Space Center, March 1995.

Alpha Station Addendum to Program Implementation Plan, RSA/NASA, 1 November 1993.

Australian Landing Sites Evaluation and Survey, JSC-34045, Assured Crew Return Vehicle (ACRV) Project Office, NASA Lyndon B. Johnson Space Center, 22 June 1993.

Assured Crew Return Vehicle (ACRV): Technical Feasibility Study on Use of the Soyuz TM for the Assured Crew Return Vehicle Missions, JSC-34048, Assured Crew Return Vehicle (ACRV) Project Office, NASA Lyndon B. Johnson Space Center, June 1993.

Letter with Attachment, C. Vest to J. Gibbons, 11 May 1993.

Mir-Freedom Assembly Sequence, NPO Energia, April 1993.

Letter, Y. Koptev and Y. Semenov to D. Goldin, 16 March 1993.

Assured Crew Return Vehicle (ACRV): Preliminary Feasibility Analysis of Using Soyuz TM for Assured Crew Return Vehicle Missions* *Includes Evaluation of Automated Rendezvous and Docking System, JSC-34023, Assured Crew Return Vehicle Project Office, NASA Lyndon B. Johnson Space Center, April 1992.

More Information

Skylab-Salyut Space Laboratory (1972)

SEI Swan Song: International Lunar Resources Exploration Concept (1993)