TMK-1/MAVR: Red Planet

MAVR sketch schematic

Soviet-era schematic of MAVR, provenance and copyright status unknown. Please contact the author if you know of its source. 2 is the greenhouse, 3 is the drop probe for Mars, 9 the probe for Venus, 10 the telescope, and 11 the living quarters.

What it was: Two separate, competing Mars flyby/lander missions (with the same name) from OKB-1, synthesized into a Mars/Venus flyby mission that was the original purpose of the N1.

Details: Wernher von Braun was famously focused on Mars for much of his life, so it’s no surprise that there were two serious proposals to send American astronauts to our next neighbour out during his heyday at NASA. Less well-known is that Sergei Korolev was likewise enamoured of a Mars mission. When the N1 rocket was first floated in 1956, it was quite specifically intended as a launcher for Korolev’s early partner Mikhail Tikhonravov’s proposal of the MPK (марсианского пилотируемого комплекса, “Mars Piloted Complex”). The MPK spacecraft was wildly ambitious—a 1630 tonne ship requiring 20 to 25 N1 launches!—and never even got to the point of sketch plans.

The basic reason for the MPK’s enormous mass was that it was both a landing mission and relied on chemical propulsion. That implied two possible routes out of the dilemma, and in the wake of Korolev and OKB-1’s success with Sputnik, work got underway on studying both under the umbrella name of TMK (Тяжелый Межпланетный Корабль, “Heavy Interplanetary Spacecraft”). One group headed by Konstantin Feoktistov—later famous as a member of the first multi-person crew aboard Voskhod-1—studied an ion-propulsion driven landing mission, while Gleb Maksimov spearheaded a conventionally propelled flyby craft.

Feoktitsov’s TMK settled on a nuclear reactor to power a “slow but steady wins the race” approach that would spiral up, unmanned, through the Van Allen radiation belts. A conventionally launched mission would sprint through the belts and catch up, depositing cosmonauts aboard this spindly-looking ion drive-driven craft for the long journey to Mars. This arrangement initiated one “look” for Soviet and Russian long-term manned missions since then: the dangerous reactor, its engine, and the necessary cooling vanes were all arrayed along a long boom that kept them away from the fragile men aboard.

Maximov’s TMK was far more conservative from a modern perspective, and actually somewhat resembles both the MVF and Skylab. This was the option selected for moving forward. By the end of 1961 the basic parameters of the craft were settled and the mission tentatively aimed at leaving Earth on June 8, 1971 and returning on July 10, 1974—by far the longest manned mission seriously considered of which the author is aware, topping even the Triple Flyby variant of NASA’s MVF.

During coast and flyby it would have been 12 meters in length and weighed 35 tonnes—prior to Mars injection this would have been 75 tonnes including propellant, hence accounting for the lifting capability of a single N1. There would have been 50 cubic meters of space inside, split evenly between habitation and work space. A visual-light telescope for astronomical observations was attached to the side, a communications antenna to the fore, and a spread of solar panels girdled it. During coast the craft would have rotated end-over-end for a bit of artificial gravity, and during flyby there was an unmanned probe to drop off for landing. At the end of the mission a return capsule, nestled in the aft end to that point, would bring the cosmonauts back to the ground.

Both life support and food would have been dependent upon a greenhouse based on Chlorella chlorophyte algae, which was calculated to give better value for mass than chemical oxygen plants: 27 kilograms of oxygen per day per kilogram of algae. The food it made would have been supplemented partly by prepared stores. Getting this plant (no pun intended) up and running was considered the key breakthrough needed for the craft, and considerable work was done through the 1960s. Three men were sealed into a close-looped simulator ecosystem based on it in 1967.

A mockup of the MAVR (MArs-VeneRa) itself—as TMK-1 was renamed once a Mars/Venus flyby path was found that was shorter than the 1000-day mission mentioned above—was begun in 1964 but foundered due to zero funding.

What happened to make it fail: MAVR was ready to roll at exactly the wrong time. Khrushchev had grown disenchanted with Korolev’s follow-up to the R-7 missile, the R-9, and instead was coming to favour the line of storable-propellant missiles developed by Mikhail Yangel. Vladimir Chelomei jumped on this and proposed his own set of manned spacecraft, one of which was for interplanetary voyages, after poaching engine designer Valentin Glushko from Korolev to build his own rockets.

By the time Korolev regained control of the Soviet manned space program he and his nation’s leaders had decided that the gauntlet thrown down by Kennedy for a race to the Moon was serious, and moreover that they should pick it up. The N1 was “stretched” to become a Moon rocket, the Mars mission was put off into the indefinite future, and the rest is history.

What was necessary for it to succeed: Getting people to Mars has turned out to be far harder than expected, so the breezy optimism that had the MAVR at Mars by the mid-1970s is hard to sustain. A lot of things went against it: the early-60s infighting in the Soviet space program, uninterest in space on the part of the Soviet military, Korolev’s egotistic insistence on going head-to-head with Apollo, the shift in the USSR’s manned spaceflight focus to shuttle and space station during the 70s…the list goes on.

One thing that would have cleaned up a lot of them, or at least softened their impact, was the transfer of the space program away from the Soviet military, in particular the GRAU which funded the rockets. They wanted missiles not launch vehicles, and so logically if Khrushchev has been serious about wanting a space program he would have accepted a proposal from Korolev made post-Sputnik that OKB-1 be reorganized as a civilian organization like NASA. It didn’t happen.

One more note: long-time readers with good memories might have noted that the initial dates selected for the mission (though it was extraordinarily unlikely that the Soviets could have hit their targets) were roughly similar to those mentioned in our discussion of the NASA Mars-Venus Flyby. As mentioned in that post, there was a tremendous solar flare in 1972 that, by NASA’s estimate, would have hit anyone outside of the Earth’s protective magnetosphere with roughly 4 grays of radiation, with death resulting in the next few weeks.

A fine image of what MAVR might have looked like as it passed Mars can be seen on the Deviantart page of Polish artist Maciej Rebisz.

Plymouth Rock: 405 Years and Counting

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The Plymouth Rock mission would have taken two Orion MPCV spacecraft, one modified for extended life support, and turn them into a single spacecraft that could undertake a six-month long mission to a small Near-Earth Asteroid. Promotional image courtesy of and ©Lockheed Martin. Click for a larger view.

What it was: A 2009 proposal by Lockheed Martin to use its Orion manned space capsule as the core of a deep space mission to the Near-Earth Asteroid 2008 EA9.

Details: Until the turn of the 21st century there were three commonly assumed steps to manned space exploration: Earth orbital, then the Moon, then the planets. While the physical gap between the first and second of these is considerable, it’s nothing compared to the step that follows. The average distance to the Moon is 384,400 kilometers; Mars never approaches the Earth to less than 54.5 million kilometers and the nature of orbital mechanics means that the path taken by any reasonable spacecraft going there must be much longer. There are several reasons why there were just eight years between the first man in space and the first Moon landing while it’s been more than four decades since with no sign of a Mars mission, but that gap is one of the biggest.

Meanwhile in recent years Lockheed Martin has been building the Orion Multi-Purpose Crew Vehicle (MPCV), an Apollo-like spacecraft built around a Crew Module and a Service Module that is currently due to make its first unmanned flight in 2014. True to its name, the Orion is supposed to be adaptable enough that it can be used for all of the missions that NASA might reasonably fly in the future, and in search of more business Lockheed has been keen to suggest ones of its own.

Plymouth Rock was one of their suggestions for the Constellation Program that began in 2004. It looked to bridge the gap between the Moon and Mars by focusing on something we’ve learned about the solar system in the last few decades. In 1980 there were fewer than twenty known asteroids that approached the Earth significantly more closely than Mars (“Near-Earth Objects” or NEOs), but as of November 24, 2012 advancing astronomical technology and fear of a reprise of the impact that killed the dinosaurs had inflated that number to 9946. Why not visit one of them somewhere out past the Moon? Not only would it increase general scientific knowledge, it would let NASA test out the technology that’s going to be needed to support astronauts on a trip to Mars without having to commit to a year or more’s travel like a full-fledged Mars mission would need.

Lockheed Martin selected 2008 EA9 as the mission’s destination, with the caveat that this selection was highly dependent on the launch date and any of a couple of dozen small asteroids might serve as a substitute. The sole criterion was that the target had to have an orbit particularly similar to Earth’s, which meant that none of them was at all notable: none even had a formal name, just a serial number, and none was larger than 75 meters in diameter. 2008 EA9 itself is approximately ten meters across.

A plain Orion wasn’t going to do the job, as it was designed for two weeks of support to the Moon and back. So a modified second Orion—the Deep Space Vehicle—would also go along for the ride. It would have been put on top of an Ares V rocket, which would have lifted it and an attached injection stage (the Earth Departure Stage, or EDS) with propellant into Low Earth Orbit. A smaller Ares I would have launched the regular Orion shortly thereafter; only two astronauts would be aboard rather than the up-to-seven that the Orion could house in Earth orbit, simply because more than that would eat through the mission’s supplies in less time than it would take for the trip there and back.

The two Orions would dock nose-to-nose in orbit and the EDS would be fired to push them on their way. Once it was out of propellant the stage would jettisoned and the Plymouth Rock spacecraft—one imagines it inevitably would have been named Mayflower—would deploy four large solar panels and begin a 92-day outbound journey. This was the other reason for only having two astronauts: each would have only 9 cubic meters to live in during the trip.

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A geocentric view of the Plymouth Rock mission’s trip to and from 2008 EA9 as it approaches Earth in late 2019. Promotional image courtesy of and ©Lockheed Martin. Click for a larger view.

Roughly 12 million kilometers later the ship would arrive at 2008 EA9 and take up station about 100 meters away. The asteroid’s mass would be so small that there would be no need to worry about its gravity, to the point that the astronauts could spacewalk over to it at will, depressurizing one of the Orions whenever they needed to enter or exit their craft.

Only something resembling the MMU “jetpacks” from the early days of the Space Shuttle would be needed to explore the asteroid as it’s likely that the tiny world’s rotation would produce centrifugal forces stronger than its gravity. Altogether this would produce a negative net force pushing anything that touched 2008 EA9 back off the surface again. This is actually a point in 2008 EA9’s favour as many asteroids are believed to be rubble piles held together by nothing more than their mutual gravitation, an arrangement that would be dangerous to explore. If 2008 EA9 spins like it’s believed to, though, it must be a solid object and so relatively stable.

After five days of exploration the astronauts would fire the engines on the modified Orion and begin their return home. This would take them another 95 days and, upon arrival at Earth, they would abandon all of their craft except for the conventional Orion’s crew capsule, which would take them down to Earth.

What happened to make it fail: As originally conceived Plymouth Rock would have been part of the Constellation program, and relied on the program’s Ares I and V rockets. With the cancellation of Constellation budget in October 2010, the mission could not go ahead as planned.

What was necessary for it to succeed: A mission to a NEO was considered one of the “big three” possible missions for Constellation (along with a return to the Moon, and a mission to Mars). While NASA tended to show it as one based on an Orion mated with an Altair lander—Constellation’s equivalent of an Apollo LM—Lockheed Martin was probably in the right in contending that two Orions were the way to go. Very few asteroids that approach Earth have noticeable gravity, so a lander would be an expensive way to do something that could be done with an astronaut on EVA instead.

As a result, Plymouth Rock likely would have gone ahead sometime around 2020 to 2025 if Constellation had continued. That said, it may be not entirely dead yet. Constellation has been replaced by the Space Launch System, which is different in detail from the earlier program but similar in broad strokes. The Orion itself is still going ahead as the manned spacecraft for SLS, and so it would be easy enough to launch a close facsimile of Plymouth Rock—though probably all in one shot aboard one of the Block IA SLS rockets being developed, as they have the throw weight to do so rather than taking two launches as per the original mission design.

Interestingly it appears that NASA may actually be interested in doing so. As of this writing a Moon landing has been taken off the list of first exploratory missions, with a lunar orbiter likely to be the first and rumours of a small station at the Earth-Moon L2 point to follow. NASA is studying a similar mission they call “Asteroid Next”, but as late as last week Lockheed Martin was still proposing a “Plymouth Rock” with a new date (2024-2025 or 2029) and a different target (either 1999 AO10 or 2000 SG344, depending on the mission date).

The latter target is an interesting choice as there’s some chance that 2000 SG344 isn’t an asteroid at all, but instead the upper stage of Apollo mission rocket abandoned in orbit and lost until its rediscovery a decade ago. If NASA does pick up on the modified Plymouth Rock then that’s something that will have to be determined before any launch in 2029.

A simple animation of a Plymouth Rock mission showing the joint Orion craft travelling to 2000 SG344 (one assuming that it’s a natural asteroid) can be seen here on YouTube.

Gemini Lunar Flyby: Always the Bridesmaid

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The most ambitious of three different proposals to fly a Gemini by the Moon, all made during the Gemini’s short heyday of 1964-66. This version of the capsule would have been mounted on an Agena-D rocket stage that could brake it into Lunar orbit and then send it back to Earth. The Gemini/Agena in turn would have been mounted on a Centaur for the initial trip from Earth orbit to the Moon. Image from Gemini Applications for Lunar Reconnaissance. Click for larger view.

What it was: A series of 1964-65 proposals to use the Gemini capsule as the core of a manned Lunar flyby mission, or even a Lunar orbiter.

Details: NASA was committed to the Apollo spacecraft for journeys to the Moon, and had begun development on it before work began on the Gemini. At first Gemini had been intended solely to build on the Mercury program (it was originally named “Mercury Mark II”), as a way of giving astronauts practice in the orbital docking and spacewalking techniques they’d need for the Apollo missions. Jim Chamberlin did try to sneak two circumlunar flights into the original Gemini plan of August 1961, but they were gone in a week; he’d try again with a Gemini Lunar lander in 1962, and still get nowhere. In essence the program was just supposed to fill the relatively short time between the last Mercury flight on May 15, 1963 and the flight of the first, unmanned Apollo sometime in 1966.

But then the Gemini proved itself to be a capable little spacecraft. From March 1965 to November 1966 it was flown on twelve missions with only one partial failure, Gemini 8. Both McDonnell Aircraft (which made the Gemini capsule) and Martin Marietta (which made the Gemini launcher, the Titan II GLV) had been shut out of Apollo and so they set about making the plausible argument for a Gemini Lunar flyby again rather than have NASA trust entirely to the as-yet untried Apollo spacecraft.

And so it was that one proposal from McDonnell dropped on to NASA desks in April 1964, shortly after the first unmanned Gemini flight. Another came in from Martin Marietta in July 1965—right in the middle of Gemini’s successful run. Both were based on the premise that the Moon landing was going to happen with Apollo no matter what they said, but that a prior Lunar flyby was still an open question.

gemini-flyby-reconnaissance

The alignment for the Earth, Sun, and Moon for the flyby mission that would give maximum coverage of the Lunar far side while also allowing photography of the proposed Apollo landing on the Sea of Tranquility. Image from Gemini Applications for Lunar Reconnaissance. Click for larger view.

McDonnell’s proposal was actually three wrapped up into one, unified by the goal of performing Lunar reconnaissance for the Apollo landings. The least ambitious of these was a single-flyby spacecraft made up of a modified Gemini capsule, the base of which was mated to a Centaur rocket stage. By not loading the Centaur entirely with propellants this arrangement was just light enough that a Saturn IB could lift it into Earth orbit while still providing enough propulsion to send it on a free-return trajectory around the Moon. There it could either focus on photographing the Sea of Tranquility while also photo-mapping the Lunar far-side to an extent, or alternatively it could look at those two targets with the opposite priority. In return for getting only one pass at the Moon and having to cut down on the amount of fuel the craft carried, this proposal had the advantage of being a single-launch, no-rendezvous mission.

Next, McDonnell proposed two missions that used two launches instead, but with the compensating advantage of putting the craft into Lunar orbit so that much more mapping was possible. The first put the Gemini—with a modified service module—base down onto an Agena-D rocket stage, a combination that could be launched into low Earth orbit together by a Saturn IB. A second Saturn IB would be used to send a Centaur rocket into orbit, and then the Gemini/Agena would dock nose-first into it. The Centaur would fire and send the Gemini/Agena into a translunar trajectory, then separate once its propellant was spent.

68 hours later the Agena would fire and bring the ship into a 150 × 20 kilometer Lunar orbit, with the perilune arranged over the proposed Apollo landing site so that it could take extremely high quality photographs of the area. After 24 hours of orbiting the Moon and shooting pictures, the astronauts would fire the Agena again to head back to Earth. There the Gemini would separate from the spent rocket stage and splashdown, returning the crew home just shy of a week after they left.

The second of McDonnell’s orbital proposals was quite similar, the major difference being that instead of using an Agena-D as the Lunar orbital and return stage this version had a massively altered service module carrying its own engines. There’d be extra development time and money needed for this version of the mission, but in return it saved almost 700 kilograms in launch weight to supplement the thin margin for error involved in launching the Gemini/Agena combination aboard a Saturn IB.

A bit more than a year later Martin Marietta moved in with their proposal. As the manufacturer of the Gemini’s launch vehicle, their idea didn’t have anything to do with a Saturn rocket. This was a real problem as Martin Marietta launchers could at most, assuming a Titan IIIC with its strap-on boosters, lift some 13,100 kilograms into orbit (contrast that with the Saturn IB’s 21,000kg). Accordingly there were no Lunar orbiters here, and even the Lunar flyby required two launches. Of course from Martin Marietta’s standpoint this was not a problem: they were more than willing to sell NASA two Titans if that was what it took.

In fact they even managed to work in a third. Not only would the Gemini launch by itself on a Titan II GLV and the Lunar injection stage on a Titan IIIC, the injection stage itself was not an Agena or a Centaur, but rather another stripped-down Titan III upper Transtage (its specific name, confusingly enough, since it’s just one example of a trans-stage used throughout the years) mated to an Agena docking adapter.

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The Gemini docked to the Titan Transtage that would push it into a flyby orbit. Note how the astronauts had their backs to the direction of travel; in contrast to the Lunar orbiter shown above, the Gemini flyby missions pushed the capsule backwards to its destination. Image from Rendezvous Concept for Circumlunar Flyby in 1967, Click for a larger view.

Despite the different equipment, this meant that the mission they proposed was essentially a recapitulation of Jim Chamberlin’s 1961 proposal—one presumes that they were hoping that the at-the-time recent success of the Gemini and the Titan II GLV would override James Webb’s veto. If it did and the mission flew, the idea was to launch the Transtage and the Gemini within a few minutes of one another (or, if absolutely necessary, launch the Gemini after the trans-stage had made most of one orbit and was coming back over Cape Canaveral). After maneuvering their capsule into the vicinity of the Transtage the astronauts would dock their Gemini nose-first to it and then use it to fire them into a free return orbit around the Moon.

Perhaps because they’d heard nothing encouraging back from NASA in the year since they’d made their own proposals, McDonnell backed this mission too; the pair even managed to rope in Pete Conrad, who would soon fly on Gemini 5, to advocate for them in a meeting with NASA’s top people on June 24, 1965. Like the earlier McDonnell proposals, Martin Marietta aimed to perform the Lunar flyby sometime in 1967, in April to be precise, and do it for US$350 million.

What happened to make it fail: McDonnell’s proposals likely went nowhere because they backed the wrong horse when they pitched them as Lunar reconnaissance missions. NASA already had plans for site mapping using the Lunar Orbiters and even a back-up plan using Apollo, the LM&SS. The latter was actually handled in part by Lockheed, and so it’s unclear why they thought NASA needed a back-up for the back-up.

Martin Marietta’s attempt failed for a more fundamental reason. They quite astutely positioned theirs as a spectacular, primarily for the purpose of beating the Soviet Union to a Lunar flyby. This was bound to pique some interest because at the time NASA’s attitude was that they were going to lose that particular race; the Moon landing had been specifically selected in 1961 as the first major one that the US could definitely take from the Russians. In the actual event it turned out that the Zond program was in trouble and Apollo 8 would take this particular laurel, but hindsight is 20/20.

As a result, NASA was supremely focused on Apollo and the Moon landing. In stark contrast to the shambolic Soviet program in the mid-60s, they picked their goal and their program and they stuck to it. While there was some late sentiment for an early flyby with a Gemini, NASA’s upper management felt it would be a distraction. There was only so much money and, more importantly, so much engineering talent in the organization, and looking away from the Moon landing to anything else was just going to delay their final goal. They were willing to give up a Lunar flyby if it got them the manned Moon landing instead. History, in both the American success with Apollo and Soviet failure with their equivalent of the Gemini Lunar Flyby, Zond, suggests that they were right.

What was necessary for it to succeed: Any of these missions could have flown if it had been only a matter of technical specs.  Their margins for error were slim, and there was a good chance that they would have lost a crew, but all four possibilities were well within NASA’s capabilities.

Some organizational impulse toward flying them was all that was really necessary. Ultimately it comes down to the fact that NASA had conceded the Lunar flyby race to the Russians already, and felt no need to go all out for one. If they beat the Soviets with an Apollo flyby, so much the better, but they weren’t going to deviate from that plan. It likely would have taken considerable external political pressure to cause a deviation—how you generate this is up to you. While Pete Conrad was able to fire a little interest for the Gemini flyby in Congress in the real world, James Webb was able to tamp it back down again.

Conrad did get one little victory out of his advocacy for a Lunar flyby. When he flew his second Gemini mission, Gemini 11 in September 1966, his goal was to dock with an Agena—as was usual in Gemini rendezvous tests. Conrad was, however, given permission to use the arrangement to boost himself and Richard Gordon to an apogee of 1369 kilometers. It was a miniature version of the mission he had wanted to fly a year previous, and set the record for a human being going furthest from the Earth. Apart from the Apollo missions to the Moon that followed, it still holds that record.

Fuji: Bringing the Mountain to the Masses

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Fuji’s Standard System configuration, showing its three components separating for re-entry. The crew would return in the saucer-shaped Core Module, centre, while the propulsion and habitation modules would be allowed to burn up. The Core Module could also be flown solo, in Fuji’s Minimum System. Based on an image from NASDA/JAXA. Click for a larger view.

What it was: A Japanese proposal to develop a manned space capsule as part of an effort to produce an “open architecture” for space travel, announced to the public in September of 2001. Intended to be launched on a Japanese H-IIA rocket, or an Ariane, or a Russian rocket (and even conceivably an American one), it would start with a very wide and flat ballistic capsule suitable for short LEO missions. It would soon be extended with a habitation module and a propulsion module for longer missions and missions to higher orbits.

Details: In 2003 China became the third country to launch a person into space entirely on its own accord. The surprising thing is that it took so long for the Astronaut Club to grow from two to three. The first two countries to qualify did so over a period of a few weeks in the spring of 1961, and then it was another 42 years before they had any company.

By the late 1980s both the European Community and Japan had active space programs and, at first blush, the economic heft to match the USA in 1961—but both failed to take advantage of it. The rise and fall of the European spaceplane Hermes is for another time, as is the strikingly similar Japanese HOPE, but in the particular case of Japan they also made an attempt at a simpler manned spacecraft. While it came along sufficiently late in the day that they wouldn’t have beaten Yang Liwei into orbit, Japan could have had a way into space during the second set of Shuttle-disaster doldrums to hit the United States, and be in an interesting position to get their own astronauts to the ISS (one module of which is Japanese) afterwards.

The Fuji spacecraft was proposed in a way that tried to address the main reason why Europe and Japan didn’t come up with their own manned space programs: there’s as yet no good economic reason, and very few scientific reasons, for people in low Earth orbit. Without the additional boost to nationalist pride that the 1960s USSR, 1960s USA, and 2000s China felt to be valuable, a manned space program in the late 20th century and early 21st produces poor returns that bring out the budgetary knives when a country’s economy hits some bumps. It’s no coincidence that the ESA and Japan’s best efforts towards manned spacecraft took place in the salad days of the late 80s and early 90s.

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The extremely wide command module of the Fuji spacecraft. Click for a larger view. Image copyright NASDA/JAXA.

The Minimum System was the simplest form of Fuji. It was a ballistic capsule intended for three, the Core Module (CM), four meters in diameter and only about a meter and a half tall—in other words a very flat shape that resembled an Apollo Command Module that had somehow got itself run over by a steamroller. It’s also reminiscent of the lenticular (read: saucer-shaped) re-entry vehicles considered in the early days of American spaceflight.

The strange shape was driven by one of Fuji’s design goals. The proposal specifically describes the original astronauts and cosmonauts of the 1960s as “supermen” because of their ability to withstand and even work while experiencing high-g forces. Fuji’s designers considered this unacceptable as they wanted to defray the cost of running the system by allowing for commercial passengers of average health. By re-entering at a high angle of attack the Core Module could generate lift and keep the stress on its crew down to 4 gravities.

The Fuji proposal was fairly general, as a full design was to wait until funding was received from the Japanese government, so the mass of the capsule is uncertain. However, the proposal depicts the cheapest possible Fuji mission having an Economy version of the CM share its launcher with a similarly sized commercial satellite from a paying customer, and the launcher is clearly a two-strap on-booster H-IIA, which means it could only lift 10 tonnes into LEO. If the capsule took half of this, it would have been comparable in size to the Russian Voskhod and about 25% smaller than a Soyuz. The former of these could accommodate three people only by sending them in a “shirtsleeve” environment and even the first few varieties of Soyuz couldn’t contain three people in spacesuits, so it’s likely that Fuji would have done the same—especially because the plan was to fly the Economy version with a crew of one and four commercial passengers.

The first manned Minimum System mission was to be launched by 2008, but the bare Core Module would have been restricted to no more than 24-hour missions in a 200 kilometer orbit. This isn’t very useful: if nothing else, the ISS orbits at about 400 kilometers up. As a result, once the Minimum System had been proven NASDA would have moved onto the Standard System. This would have sandwiched the CM between an Expansion Module above it and a Propulsion Module below it. In other words, while the CM may have vaguely resembled something from an American spacecraft, Fuji’s eventual arrangement was to be more like a Russian one.

The Propulsion Module would have packed fuel tanks and a rocket engine that together gave the ship 3,000 meters per second of delta-v. To put it another way, while the Standard Configuration couldn’t orbit the Moon it would have been able to do a lunar flyby in a free return orbit—which fact was also touted as helping keep the program economical by being a commercial draw. Little was said about the Expansion Module, other than it being more volume for the crew to inhabit outside of launch and re-entry; there is a quick mention of attaching robotic arms to it so that Fuji could be used to repair satellites or as a manned space station construction runabout.

The goal for the Standard System was to have it up and running within four years of the first successful Minimum System flight—in other words, 2012 if everything went right.

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Fuji’s Core Module returning its crew to Earth under a steerable parafoil rather than a parachute. Based on an image from NASDA/JAXA. Click for a larger view.

At the end of any mission only the Core Module would return. After reaching subsonic speeds, it would have then deployed a parafoil—an idea first considered by the US for the Gemini program but rejected for lack of time to develop it. This would have given the returning crew some ability to direct the last stages of their flight.

NASDA also added one more attempt to make Fuji pay for itself. Without much in the way of details (instead relying almost entirely on the analogy of the IBM PC architecture) they suggest making Fuji’s design as openly available as possible and encouraging the other space-faring nations to freely re-use what Japan developed. Ultimately the goal would be to turn space development into a single large market in which Japan could compete, rather than several isolated smaller ones in the US, Russia, Europe, and so on.

What happened to make it fail: Fuji was proposed just as Japan’s security in the region started becoming more tenuous. North Korea tried launching its first satellite in 1998, but many believed that it was not that at all but rather a cover story for the development of an ICBM. Similarly, negotiations to prevent North Korea from developing a nuclear weapon were going badly.

Add on to this the continuing economic growth of China (which allowed the more-than-doubling of their military budget between 1995 and 2000), and Japan would have been under some budget strain even in the best of circumstances. Yet IMF estimates say that recession and the Asian Financial Crisis of 1997 saw the Japanese economy contract from a nominal GDP of US$5.33 trillion in 1995 to a low of US$3.91 trillion in 1998—and it did not exceed the 1995 figure in any other year prior to 2010.

Accordingly the Japanese government cut spending on science and reorganized their space program by merging NASDA with two other agencies—the National Aerospace Laboratory of Japan and the Institute for Space and Astronautical Science—on October 1, 2003 to form the Japanese Aerospace Exploration Agency (JAXA). While scientific use of space has continued under JAXA they have placed a new emphasis on developing an independent Earth observation capability, apparently at least in part so they can keep a closer watch on North Korea and China without having to rely on US intelligence.

Fuji never made it out the other end of this reorganization. In 2005 JAXA proposed a different spacecraft, one that is intended to be launched on the more capable H-IIB rocket. Whether anything comes of the new plan remains to be seen, however, as it’s a very unaggressive plan to send a man to the Moon by 2025.

What was necessary for it to succeed: This is a hard one, for all that it was a perfectly reasonable spacecraft for its time and place, as two of the three reasons for Japan failing to follow through on it were about as movable as Fuji’s namesake. Japan’s economic crisis had been slowly ripening for a decade or so, while China’s rise seems nearly inevitable in retrospect—at least it doesn’t seem right to speculate on, say, a new bout of Maoist reaction in that country simply to get a spaceship to fly.

The wild card here is North Korea. After the collapse of the Soviet Union they did try for a modest rapprochement with the United States, but it foundered on American distrust stemming from the People’s Republic having broken previous two-party agreements. While it’s hard to see Kim Jong-Il sticking to any agreement for good, one with the US that lasted through the early 2000s might have given Japan a sufficient feeling of security that they would think they should go ahead with Fuji despite the contraction of their economy. This is especially true if the agreement also brought a moderate thaw to Sino-Japanese relations, as well it might have.

Even so, it seems likely that NASDA would have felt a budget crunch anyway, and that Fuji would at the very least have happened several years later than initially planned.

The Martin 410: Apollo of Santa Ana

martin-410-cutaway-diagram

A cutaway view of the Martin 410 as it would have been configured en route to the Moon (excepting the escape tower, at left, which would be ejected after launch). Note the lifting body shape of the crew compartment, and the stubby cylinder of the habitation module enclosed in the larger toroidal equipment and propulsion module. Image from Glenn L. Martin Company’s “Apollo Final Report: Configuration” delivered to NASA in 1961. Click for a larger view.

What it was: One of several formal proposals made to NASA in 1961 as part of the design competition for the Apollo spacecraft. It had certain similarities to the one that was actually built (as did all of the proposals, as they had to meet criteria set by NASA) but was primarily different in two ways. As Apollo was still pictured as a direct descent mission at the time, it didn’t use the Lunar Orbit Rendezvous technique that was used for the real missions, and the re-entry vehicle was a lifting body instead of a ballistic capsule.

Details: On October 9, 1960, fourteen different companies answered NASA RFP-302, which asked them for feasibility studies on advanced manned spacecraft for the upcoming Project Apollo. Among them were Lockheed, Boeing, General Electric, and Grumman, as well as the subject of this post: the Glenn L. Martin Company of Santa Ana, California.

Within two weeks the contest was down to three: GE, Convair, and Martin with what they called their Model 410. Up against the contractors was an internal design by NASA’s Langley Research Center, specifically their Space Task Group, which had designed the Mercury capsule. Time passed and with the agency buoyed by the first successful American manned spaceflight on May 5, 1961—Alan Shepard’s Freedom 7—May 17 saw the final proposals for all four on NASA desks and the process of evaluating and deciding between them underway.

Eight days later John F. Kennedy challenged Congress to achieve “the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth”, and things changed—the White House had had its interest piqued back in October when the study contracts were awarded and had been working behind the scenes with NASA. The Langley group rapidly metamorphosed into the much-larger Manned Spacecraft Center—now the Johnson Space Center—and by September started the move to land in Texas donated by Rice University (which is why Kennedy’s second famous space speech, the “We choose to go to the moon” one, was made there).

langley-apollo-design

The suggested layout of the Apollo spacecraft for the second phase of the competition. Note the considerable similarity to what actually got built. From Chariots for Apollo: A History of Manned Lunar Spacecraft. Click for a larger view.

Even before then, the Langley group had swung into action. Their chief engineer was Maxime Faget, an American of Belizean birth, had designed the Mercury capsule, and his head of engineering (Canadian Jim Chamberlin, formerly of Avro) was in the middle of designing the Gemini. Their job was to synthesize what the contractors had developed with their own design and use it to develop a new set of specifications—in actuality, a nearly complete design of its own—that could meet Kennedy’s challenge. While the three previous contractor proposals had been paid for by NASA to the tune of US$250,000 apiece (though all of them took a loss, spending in excess of $1 million apiece), the other contractors had been encouraged to carry on with their work on their own. This attitude now paid off: a new competition was begun for a final design, open to all groups who’d tried back in October not just the three previous winners. On July 28 twelve contractors (two had dropped out back during the first phase, Cornell and Republic Aviation) were asked to submit again based on the new prerequisites. Several of the contractors teamed up with each other, reducing the number of replies to five, but Martin once again went with the M-410 on their own.

Not counting the rocket adapter ring (which all the proposals had so they could mate to the upper stage of a Saturn), the M-410 was made up of three parts: a command module for use any time an engine was burning and for re-entry, a mission module in which the crew would live at other times, and a composite equipment and propulsion module.

The command module was the most interestingly divergent component compared to the Apollo spacecraft that actually got built. All three contractors evaluated ballistic, winged, and lifting body re-entry vehicles. The latter was a particular one NASA called an M-1, and Martin went above and beyond by evaluating a number of other shapes in all three categories before settling on a variation of the M-1. Their solution made the M-410’s re-entry moderately controllable, especially as it would have had four control flaps; Martin considered this a big improvement on Mercury or the Soviet Vostok. It would have been built out of aluminum alloy, and had a composite heat shield made out of ablative material and a superalloy (undecided at the time, but something like René 41 or an Inconel). The version of the M-410 submitted post-Kennedy’s speech was also unusual because of the four rectangular flaps that would deploy from its underside, which would expose solar panels to power the craft. During launch the command module had an emergency escape tower perched on top of it, though this would be jettisoned on reaching 90 kilometers in height.

The three crew would live for the majority of their mission in the mission module. This supplied a little over eleven cubic meters on top of roughly the same for the command module (contrast this with the 12.9 cubic meters of the combined Apollo Command Module and LM).

These two were then mated to the equipment and propulsion module. As well as the usual electronics for a Moon-bound manned spacecraft, it packed a single LR-115 engine (a design which later evolved into the R-10 and derivatives used for the Saturn I and the Centaur) and 4740 kilograms of liquid oxygen and liquid hydrogen.

Having launched in an unspecified way (NASA was still trying to decide if they were going to use multiple smaller rockets to establish a fuel depot in orbit, or go as they actually did with a larger rocket like the Saturn V), Martin suggested that the M-410 be sent on its way to the Moon using a lower stage attached to the rocket adapter ring. This stage would have contained roughly 13 tonnes of LH2 and LOX and been pushed by three LR-115s.

This was powerful enough to get it down to the Moon, because the entire thing was designed to land there. Exactly how this was to be accomplished remained to be seen, as NASA was then in the middle stages of its most historic argument: land directly via an Earth Orbit Rendezvous profile, or send a separable landing module and rendezvous above the Moon. Going in to the proposal period it was assumed that the former was likeliest, though the contractors were asked to consider what they would have to do if the latter won (as, of course, it did).

artificial-gravity-on-the-martin-410

One of the ideas studied, but explicitly rejected, for giving the M-410 artificial gravity: spin it up using the booster stage as a counterweight. From “Apollo Final Report: Configuration“. Click for a larger view.

Assuming it did land directly, though, the lower stage would be left behind as the propulsion module had sufficient thrust to lift itself back off the Moon and home to Earth. One thing the lower stage would not be used for was the generation of artificial gravity—Martin took the time to figure out if it were possible to generate a bit of it during the mission, including putting the lower stage out on a tether and using it as a counterweight to spin up the rest of the craft. They decided that for a trip as short as one to the Moon it wasn’t worth the extra weight needed for systems that could pull the trick off.

At the end of the mission, the command module would separate from the rest of the craft and re-enter. The M-410’s CM lifting body was designed to touchdown on water or land, with a combination of parachutes and retrorockets slowing it to just one meter per second as it touched the ground.

What happened to make it fail: On October 9, 1961 the new proposals were received, and two days later the five competing contractors gave presentations on their work. The evaluations began immediately thereafter, and were completed on October 28th. At the end of the competition, the M-410 was first with an average score of 6.9 points in each of the categories that NASA had outlined. Next came General Dynamics and North American Aviation, tied for second with 6.6 points; the GE-led and McDonnell-led contractor coalitions were the also-rans.

Despite the win Martin lost the contract to North American on November 28, 1961; NAA would go on to build the actual Apollo CSM. NASA administrator James Webb and his deputy Robert Seamans justified their decision on the basis of an external factor: NAA’s experience building the X-15.

The real reason is widely believed to be that North American had made the conscious decision to stick as closely as possible to Max Faget’s post-synthesis Langley design, and that NASA wanted that regardless of the merits of any other approach. Faget reportedly had been annoyed by the fact that none of the three initial designs had gone for a blunt-body re-entry vehicle, which was why he had come up with the Langley design in the first place and then convinced the agency to re-open the competition. He then had enough influence to disqualify any bid that didn’t follow his lead, including the Martin 410.

From this point onwards (and most noticeably in the proposals for the Space Shuttle a decade later, excepting the oddball SERV) NASA contractors understood that the implicit rule in any spacecraft design competition was “What Max Faget wants, Max Faget gets”. Despite the obvious possibilities for disaster with this approach giving him a veto turned out to be a pretty good idea: history has proven Maxime Faget was a talented spacecraft designer, arguably the best ever.

What was necessary for it to succeed: Not an awful lot more than what actually happened—the M-410 is one of the likeliest “what-ifs?” of the Apollo program.  It won the Apollo design competition, and if a small number of people (Faget, Webb, and Seamans) hadn’t been able to shift the results arbitrarily, it would have gone ahead. There would have been changes made, as happened in the real world to NAA’s design between 1961 and the first completed Block II Apollo craft flown in October 1968, but otherwise this design could have gone to the Moon.

Mars Expedition 1969: NASA’s Waterloo (Integrated Program Plan, Part I)

A cutaway view of the Mars craft proposed by MSFC in 1969.

A cutaway view of the Planetary Mission Module (centre) and Mars Expedition Module (right) on top of the Nuclear Shuttle (fully visible on the second ship in the background). Public domain image from the Marshall Space Flight Center, NASA. Click for a larger view.

What it was: NASA’s follow-up to the Apollo program. A manned mission to Mars would have been launched in November 1981, brought twelve men to Mars—six of them landing—and then returned to Earth in August of 1983 (with a flyby of Venus along the return route). There would be two more manned missions by the end of 1985, and a manned base by the middle of 1987.

Details: Neil Armstrong stepped onto the Moon on July 21, 1969 and the obvious next question was “Now what?”

NASA had been answering it intermittently for years prior to this but now they got down to business. In particular, while they supported the Apollo Applications Project they were not content to stick to those missions’ main goal: to find out new things to do with the hardware they had already developed. Quite reasonably they decided that they needed to carry onwards and upwards with their engineering. Not only was a manned mission to Mars the obvious next step from an exploratory standpoint, it had the advantage of requiring that they move beyond Apollo equipment.

To that end they turned once again to Wernher von Braun. This was the culmination of his life dream: he’d published a Mars program in 1948, made a splash with the variant of it published in Collier’s in 1954, come up with another smaller expedition in 1956, and then sponsored the so-called EMPIRE and UMPIRE studies in 1962-64. On August 4, 1969 he made a presentation of what would be his final Mars proposal to the Space Task Group (STG), chaired by Vice President Spiro Agnew.

The mission was to be the penultimate part of a two-decade effort, the Integrated Program Plan, which could really be thought of as “Apollo 2.0”: another vast effort with an end goal, designed to replace the one that had just finished. As such it was part of an integrated whole that developed orbital operations into a finely tuned science, first by practicing with the Apollo Applications Program space stations and lunar base. One of the tools was to be a new space-only booster based on NERVA—which is to say, the first ever nuclear thermal rocket. This piece of equipment, dubbed the Nuclear Shuttle, was intermediate in mass between the second and third stages of a Saturn V, and had a higher specific impulse than any rocket ever flown.

Individual Nuclear Shuttles would be fueled in orbit with liquid hydrogen and used to push men and cargo to the Moon, then the empties returned to Earth orbit when they could be refueled and used again—up to ten times in all. Regular Saturn V launches would occur all through the early to mid-70s, building a space station and generally preparing the necessary infrastructure to be a “gas station”.

Meanwhile the other necessary equipment would be tested as part of an Apollo Moon base (basically a revival of the ALSS Lunar Base, which had been cancelled when new Saturn V production went into hiatus). There would be tests of the Nuclear Shuttle by the end of 1977, and 25 men living on the Moon by 1982.

With all that shaken out, the Mars mission would begin on November 12, 1981 with two ships launched on a Mars-bound a trajectory from low-Earth orbit. Each would consist of three Nuclear Shuttles strapped in tandem and a Mars craft made up of a Planetary Mission Module (PMM) habitation section and a Mars Excursion Module (MEM) lander mated to the tip of the one in the centre. The two side Shuttles would get the centre one and its payload up to speed, then peel loose and re-enter Earth orbit for reuse, while the two diminished mission craft would carry on their way.

There were two because the mission had the unique profile of backing itself up. Strictly speaking only one would be necessary for the mission, but the second would fly in formation to be a lifeboat in the case something went horribly wrong on the first—and the first served the same purpose for the second.

This kind of redundancy was necessary because the mission’s twelve crew were going to be away a long time. They’d arrive at Mars on August 9, 1982, stay there for almost three months, and then return to Earth for August 14, 1983: 640 days in all. In theory you wanted to minimize the weight of what you sent, but no margin for error meant nothing could go wrong without endangering the whole mission. NASA had always operated on the principle that you needed something to work with in case of an emergency, a principle that would prove its worth a few months after von Braun’s presentation when one whole side blew off of Apollo 13’s CSM and the astronauts on board were able to ride the excess margins back to Earth. Away from Earth for far longer than any space mission flown to that point, the Mars expedition would get its margin by literally flying two missions at once.

While at Mars six astronauts would stay aboard the PMM and Nuclear Shuttle combinations, flying in an elliptical orbit (a clever innovation by von Braun which made docking harder but cut the mass needed for the mission in half). After a remote sampler determined that it was safe to descend, six more astronauts would go to the surface in two groups of three aboard the Mars Expedition Modules, a capsule derived from the cone-shaped Apollo Command Module. They would slow down in what had only recently been discovered to be Mars’ very thin atmosphere by combination of a parachute, a ballute (a balloon-shaped inflatable parachute that works well at low atmospheric densities), and finally retrorockets starting three kilometers up.

Cutaway view of a MEM

Cutaway view of a MEM lander. Public Domain image from NASA’s Humans to Mars: Fifty Years of Mission Planning, 1950-2000. Click for a larger view.

A MEM could support its crew on the ground for up to sixty days, then its upper stage could climb back into orbit for rendezvous with the PMMs and Nuclear Shuttles. The latter would then fire up one more time and start the long journey back to Earth on 28 October, 1982.

The mission was not quite done, however. Their trajectory would take them back inside Earth’s orbit on a flyby of Venus on February 12, 1983. While this was a second opportunity for scientific study, it was primarily a speed-shedding maneuver. Four probes would be dropped on the way by.

Having got the right trajectory and speed, the two Mars craft would pull into Earth orbit where they would dock with the space station (while not the Orbiting Quarantine Facility, which was proposed several years later, it would serve the same purpose). From there they would be picked up by the Space Shuttle for the last leg of the journey home. If for whatever reason the space station didn’t exist or wouldn’t be suitable for this, the mission could be designed instead with an Apollo-style command module would let the crew splashdown directly to Earth.

Note that four of the Nuclear Shuttles had returned to LEO near the start of the mission; now the last two had done the same and so had their associated Mars craft. Only the MEMs would have been used up. Accordingly the ships would be refurbished and sent out again in 1986. Meanwhile, a second pair of ships would have been launched early in 1983, and on return be re-launched in 1988. By mid-1989, the intention was to have a 48-man semi-permanent base on Mars.

Bearing in mind that the proposal was part of a larger manned space effort including the Space Shuttle and a Moon base, the total cost of NASA’s programs was estimated about US$7 billion per year through at 1976 and $8 to 10 billion for the few years after that. The Space Task Group accepted von Braun’s Mars proposal and the NASA Integrated Program Plan as a whole, and passed it on to President Nixon on September 15, 1969.

What happened to make it fail: There was an utter disconnect between what NASA thought they should get in funding and what everyone else in the government was willing to give them. Even the Space Task Group was uneasy about the von Braun plan and offered two decompressed (and cheaper) versions of it—one where the Mars landing didn’t take place until 1986 and another where the landing was the goal but there was no set date for it. They still underestimated the opposition they would face.

Mariner 7 flew by Mars the day after von Braun made his presentation to the Space Task Group, and appeared to back up what Mariners 4 and 6 had shown previously: that Mars was a dead world, cratered not overly different from the Moon. We now know that by bad luck these missions happened to photograph the most inhospitable parts of Mars rather than the (slightly) more Earth-like northern Hemisphere, but that realization was in the future. Initial jubilation over Apollo 11 faded within a few months in favour of hard questions about why men had to go to Mars in light of what had been learned.

There was also a strong sense among the public and politicians that the United States had to get its house in order down on Earth. Protests against the Vietnam War were at their height and the country was still reeling from the urban riots of 1968. The Republicans had been voted back into power in the presidency in response (though the Democrats still controlled Congress) and Nixon was to continue the squeeze on the NASA budget that his Democratic predecessor had begun. When his director of the Office of Management and Budget Robert Mayo—an observer on the STG—objected to NASA’s proposal for FY 1971 coming in 29% over the cap he had imposed on them (US$4.5 billion instead of $3.5 billion) he convinced Nixon to put his foot down and NASA’s entire manned space program entered a death spiral.

By the time the dust settled almost all of von Braun and NASA’s programs had been cut. On March 3, 1970 Nixon announced that he’d allow only a truncated Apollo program, one space station (Skylab) and a commitment to the Space Shuttle. NASA would try one more Mars proposal in 1971; Wernher von Braun left NASA in 1972 and died in 1977 even before his proposed mission would have launched.

What was necessary for it to succeed: Almost everything was pointing against a Mars mission being approved in 1969. Public opinion was dubious (a Gallup poll in July 1969 found 53% of Americans against it—as Apollo 11 was going on!), the political interest to explore space was fading away in the Democratic Party as John F. Kennedy receded into the past, and Nixon was struggling with paying for the Vietnam War just as the US economy was sliding into recession. After his presidency various inside sources reported that he had been looking for a way to wrap up Apollo without looking like “The Man Who Killed the Space Program”; ironically, the less-ambitious options included in the STG’s report gave him the loophole he needed to dive through.

One possibility that could have brought about the mission would be a virtual tie in the space race, with the Americans and Russians getting to the Moon in a dead heat or possibly even the Russians getting a man on the Moon first. Under those circumstances the US might have committed to “Space Race, Round 2” and go for Mars. But this is a hard one to get flying, for all that it’s about the closest we’ve ever been to seeing a manned Mars mission. Even if it had been approved how much it would have had to shrink and delay as it rode out the 1973 Oil Crisis and the jittery economic conditions that lasted into the early 1980s is an open question.

Some very nice renders of this mission can be found on the DeviantArt page of Drell-7, AKA Tom Peters.

Manned Venus Flyby: Apollo’s Hail Mary Pass (Apollo Applications Program, Part I)

MVF Cutaway

A cutaway view of the Manned Venus Flyby spacecraft. Based on Apollo hardware, this remarkable proposal would have sent three astronauts on a year-long mission to Venus and back. Public domain image from the 1967 NASA document Manned Venus Flyby, via Wikimedia Commons. Click for a larger version.

What it was: A proposed post-Moon landing manned mission using Apollo hardware. It would have launched during a good alignment of Earth and Venus in November 1973 and taken three astronauts on a flyby of the planet Venus, returning to the Earth 13 months after launch.

A later variation of the mission ambitiously suggested using a better conjunction in 1977 to visit Venus and Mars on an outbound leg and Venus again on the Earth-return leg, however most of the work done considered the shorter Venus flyby.

Details: By the mid-1960s NASA was well aware that if they successfully completed the Apollo moon landings they would probably face a severe decline in budget for the manned space program. In the hopes of proving their ongoing worth they developed a few different post-Apollo proposals using evolutionary versions of the Apollo hardware, including plans for a manned lunar base, space stations, and planetary exploration. The latter two of these goals were at first grouped under the name Apollo X, and then became the Apollo Applications Program (AAP).

By far the most ambitious of the AAP missions was a manned flyby of the planet Venus. After two preliminary missions in Earth orbit to test the technology, a Saturn V launch would lift an Apollo Command Module into orbit. As in a typical mission, the first two stages of the rocket would be jettisoned. However the uppermost stage, the Saturn IVB, would be kept and drained of any remaining propellant. Using gear stored where the Lunar Landing Module would have been placed in a Moon mission, the astronauts would then rig it as a habitation module.

The resulting 33-meter-long spacecraft would leave Earth orbit on October 31, 1973 and travel towards Venus for 123 days. There would be a flyby on March 3, 1974. The craft would have been aimed to pass Venus as close as 6200 kilometers above the surface (one planet radius) very quickly—orbital mechanics would have it moving relative to Venus at a clip of 16,500 kilometers per hour—crossing the lit side of the planet. A sidescan radar would map the portion of the planet they could see as they flew by, and the astronauts would perform spectroscopic and photographic studies.

A series of probes was to be dropped by the spacecraft, and they were specifically enumerated in the proposal for the Triple Flyby variant of this mission that was mentioned earlier. Near closest approach the MVF would launch an orbiter and fourteen planetary probes; the probes would communicate with the orbiter, which would then beam the results back to Earth. Altogether the probes were:

  • Six atmospheric probes, which would enter the atmosphere at six locations: the planet’s solar and anti-solar points, its terminator and equator, and the middle of the light and dark sides. They would drop in ballistically and try to determine how Venus’ atmosphere increased in density the closer one got to the surface.
  • Four meteorological balloon probes. They would float in the atmosphere and try to learn how the Venusian atmosphere circulated as well as study smaller-scale winds.
  • Two “crash-landing” probes that would try to photograph the surface on the way down, much like Rangers 7, 8, and 9 did with the Moon.
  • Two soft-landers that would take surface photographs, examine the soil, and measure Venusian weather.

As well as acting as a communications hub, the orbiter would use X-band radar to map the planet.

MVF Mission Trajectory

The MVF’s trajectory. Detail from Manned Venus Flyby. Click for a larger view.

After that burst of activity the MVF craft would then return home, taking 273 days more to loop out to 1.24 AU from the Sun on a hyperbolic trajectory and eventually swing back to Earth. The astronauts’ landing on Earth would happen on December 1, 1974—total mission time would be 396 days. The Triple Flyby variant would have taken more than 800 days starting in 1977.

When not at Venus, the MVF astronauts would have studied the Sun and solar wind as well as making observations of Mercury, which would be only 0.3 AU away two weeks after the Venus flyby. To keep them occupied otherwise their habitation capsule would have been outfitted with a small movie screen (to show 2 kilograms of movies allowed), and a “viscous damper exercycle/g-conditioner”. The crew would also be allowed 1.5 kilograms of recorded music, 1 kilogram of games, and 9 kilograms of reading material. Hopefully they would choose wisely.

What happened to make it fail: The MVF was part of the Apollo Applications Program, and the AAP was killed dead on August 16, 1968 when the House of Representatives voted to cut its funding from US$455 million to US$122 million. President Johnson accepted this as part of a larger budget deal that kept NASA’s near-term goals safe, though even at that the agency’s entire budget dropped by 18% between 1968 and 1969. The only AAP mission to survive was Skylab.

What was necessary for it to succeed: It’s tough to get this one to work as it’s difficult to see any advantage to sending people on this mission. Mariner 5 had already flown by Venus in 1967 and NASA was able to send a robotic orbiter as part of the Pioneer 12 mission in 1978, just a few years after MVF would have flown.

Even the many probes that the MVF would leave behind at Venus had no obvious connection to the manned part of the mission; it would have been easier to send an unmanned bus of similar size and drop the probes that way. There would be no need then for heavy food, water, or air, or the space for people to move around. And unlike the manned mission there would be no need to bring the bus back, greatly reducing the mission’s difficulty. About all the manned mission had going for it was an opportunity to see what kind of effect a year in microgravity would have on humans, and that could just as easily be determined using a space station in low Earth orbit.

On that basis we also need to be aware that Congress asked hard questions about the purpose of NASA’s manned Mars mission plans in the late 1960s and were hostile to all of them. If Mars wasn’t going to get any money, it’s hard to see what could influence them to fund a mission to Venus.

Finally it needs to be pointed out that no matter even if the MVF launched, nature itself probably had this mission’s number. We didn’t have a very good understanding of the Sun at that time, having only observed one solar cycle from above the atmosphere when the flyby was proposed in 1967. While the launch window was deliberately chosen to be near a solar minimum, and the flyby craft was to have a radiation lifeboat in the equipment module, the mission would have run into an unforeseen natural event on the way back to Earth.

On July 5-6, 1974 the Earth was hit by a big coronal mass ejection (CME), a storm of electrons and protons thrown off of the Sun. People down on Earth were protected by the planet’s magnetic field, as usual, but the astronauts coming back from Venus wouldn’t have been so lucky. Their line to the Sun was several degrees off from the Earth’s (at the time they would have actually looped out past Earth as their trajectory slowly took them back home), but CMEs can cover quite a bit of space. Had the mission actually flown, the astronauts on-board may well have died of radiation sickness after being hit with more (and more energetic) solar protons than their spacecraft was built to handle.

The saving grace here is that coronal mass ejections were discovered in 1971, so the initial plan probably would have been called off rather than risk casualties, or at least be reconfigured to give the astronauts the protection the 1967 plan failed to give them.

An interesting simulation (using the program Orbiter) of how the MVF mission would have run can be seen on YouTube.