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I am creating an alternate history of the Space Race. Essentially the Point of Divergence from a Space Race perspective would be the Soviet moonshot efforts not failing spectacularly. Therefore they are able to put a man on the moon, and thus the Space Race continues.

My question is whether it would be tenable for NASA to carry out a manned Mars mission by the end of the 1970s. This mission would also include a manned flyby of Venus carried out after departure from Mars.

I am placing my date for the Mars program around 1979, as I think it would give enough time for research and development post-Apollo as well as long-duration missions (possibly involving Skylab) to acclimate crews for the long-term mission. I seek to find out whether that is a plausible date or not.

Another element of the alternate timeline is that the NERVA (Nuclear Engine for Rocket Vehicle Application) program is not terminated, allowing for its use in spaceflight by NASA. I also want to know whether the use of NERVA would facilitate a more efficient method of interplanetary space travel.

Worldbuilding SE's response would be greatly appreciated.

Edit by the author: bruh how does this have 3k views

Anyway, your responses generally go along the line of either 'No, crippling technological and/or physical limitations.' or 'Possible, with caveats.', with a healthy helping of 'It's worldbuilding and alternate fiction -- screw it, you don't have to justify anything.' In any case, thank you all for the valuable input.

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  • $\begingroup$ The Soviet failures at moon landing are a symptom and consequence of systemic factors. Apollo was a capstone on winning the Space Race, not the deciding factor. For detail, see the discussion here space.stackexchange.com/questions/64859/… $\endgroup$
    – Dragongeek
    Commented Aug 12 at 11:05
  • $\begingroup$ The problems with the N-1 came from organizing principles of Soviet industry. It is within the bounds of hard SF to say "the ministry of aviation was convinced to cooperate" and the N-1's design could therefore be simplified enough to fly. $\endgroup$
    – SPavel
    Commented Aug 12 at 18:42
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    $\begingroup$ similar idea is already pretty thoroughly explored in For All Mankind, might want to look it up first. $\endgroup$
    – Going Durden
    Commented Aug 13 at 7:12
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    $\begingroup$ Note that since gravity is much higher on Mars than on luna - I believe about 2.2x higher? the take off concept rom Mars would be MUCH MUCH more difficult $\endgroup$
    – Fattie
    Commented Aug 14 at 12:41
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    $\begingroup$ @Fattie umm, no? It definitely can happen and the radiation is not that big of a problem $\endgroup$
    – Seggan
    Commented Aug 17 at 14:10

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Likely.

A question of money and risk. As you pointed out, the parts are in place.

  • Gemini established the ability to rendezvous in orbit. With enough launch pads, thousands of tons can be put into orbit to assemble and fuel the craft.

  • Skylab established the ability to live in zero-G for months. Salyut made it years, using shift changes and resupply. A single crew did stay for half a year.

  • Delta-V is a question of drive technology and fuel mass. Either a conventional engine and lots of fuel, or a nuclear engine and less reaction mass.

There are propsals these days to send the mission in parts, with the return vehicle and a fuel plant confirmed on the Mars surface before the crew launches. That's probably a no-go with 1970s tech. Send all in a single manned mission.

The mission prep could include dozens of launches, with the crew habitat, engine, lots of empty tanks, the fuel, and the lander (in two parts plus fuel?).

People who come back after years in space would probably have medical problems. A relatively large craft, a relatively large crew, several surgeons among them? Either your story ends with crews in wheelchairs, after landing, or it ends with a few casualties.

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    $\begingroup$ "Either your story ends with crews in wheelchairs, after landing, or it ends with a few casualties" I think the wheelchairs are likely na inevitable, the casualties are potential but ending up wheelchair-bound for anything up to a couple of years after they return seems pretty certain with our experience with the kit we were using at the time best case scenario may be they don't spend the rest of their life using wheelchairs and walking frames after the get back and no one dies, but that they'll spend some serious time convalescing and regaining strength after they get back seems certain.. $\endgroup$
    – Pelinore
    Commented Aug 11 at 18:17
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    $\begingroup$ The real danger from weightlessness-induced weakness isn't when they get back to Earth. The real danger is if they're too weak to walk on Mars by the time they get there. It would be like if the Pilgrims had suddenly all become paraplegic the moment they got off the Mayflower. Plymouth would have failed in days, they would all be dead in a week or two. $\endgroup$
    – Ryan_L
    Commented Aug 11 at 22:53
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    $\begingroup$ That force would be less lifting from Mars. $\endgroup$
    – FlaStorm32
    Commented Aug 12 at 1:21
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    $\begingroup$ @Pelinore - Valeri Polyakov spent 437 days in space in 1994-5, the whole point of this was to test the feasibility of a trip to Mars. I can't find much information about his condition on returning, but as far as I can find he didn't end up in a wheelchair at all, he was able to walk immediately on landing. Total radiation dose was a very survivable 15 roentgens. He believed that he proved that a Mars trip is possible. $\endgroup$
    – user111403
    Commented Aug 12 at 5:10
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    $\begingroup$ @Nosajimiki True, but even with 70s tech you could put a bunch of candidates on a space station for a few months to figure out who can handle it. I imagine that with a decent dataset, you might even be able to filter and predict what physical characteristics are likely to do well (though I guess it might be random). $\endgroup$
    – user111403
    Commented Aug 12 at 20:47
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No, we did not know enough about Mars to plan for its environment

The Apollo Missions did a lot to teach people about how much we don't know about what we don't know. Lunar regolith and its damaging effects came as a huge surprise to NASA engineers. Apollo 11 and later were only a success because the astronauts were able to land, do some quick documentation and sampling, and come right back home. If they had stayed for more than a few days, the damage to their space suits and equipment would have easily turned those into 1-way missions.

With the knowledge of how hostile and unpredictable other worlds can be, NASA and similar agencies had to abandon any hopes of sending people to Mars until after they could confirm what precautions would be required to stay there in the long terms because of the 16 month window between when you can land and come back. Mars is also too far away to remote control a drone from; so, we needed to wait until computers got good enough that we could build autonomous drones capable of surveying the planet for similarly unknowable hazards to those found on the Moon. The technology for this did not exist until the late 90s; so, we could not even begin to set expectations about Martian environmental hazards until after the Pathfinder mission in 1997.

If we continued Space Race levels of funding in our pursuit of Mars, and look at the mid-70s as when we could first prove the viability of a long term space capsule (space station), we could have maybe done a manned Mars orbital mission that could drop remote controlled probes by the late 70s or early 80s, but the risk of trying to put boots on the ground in the 70s would have been too high. If we could glean by manned orbital missions what we waited to learn about Mars in the 90s, it could speed up our race to Mars by a good bit, but it would have been VERY expensive. It would probably take another 10-20 years after our first manned orbital missions to examine our findings and do all the tests needed to attempt a manned mission to the surface of Mars. I would not assume anything earlier than the 90s would be even remotely possible without a wanton disregard for human life and bad PR... and frankly, even though both nations were willing to sacrifice a few dead astronauts here and there, the risk of bad PR meant that neither side would take a chance on going down to Mars blindly in a post Apollo 11 space race.

What if they tried anyway?

The average 60-70's rocket launch experienced multiple malfunctions with many individual components having over a 1% failure rate. The only reason manned moon missions were made possible with such unreliable technology was that many of these system were designed with 4+ layers of redundancy. For NASA to get to this point meant employing engineers and project leaders who are exceptionally risk averse.

One of the main reasons historians cite for Russia's space program not beating the USA to the moon was because Russia's missile systems were less redundant which made them less scalable. Just trying to make the same old systems bigger without significant improvements in safety margins and redundancies made just getting off the ground alive an insurmountable task.

So, it's not just a question of if your 70's people might risk a blind mission, but if such a group of engineers and administrators could possibly design systems using the technology of the day to make the mission work. Any group of people willing to overlook the obvious issue of not surveying the planet first is inherently too willing to overlook some of the other 10,000 issues that you need to overcome to get your astronauts to Mars alive in the first place.

So, any space program that would give the green light to a blind mission to Mars is inherently not risk averse enough to design a ship capable of surviving the trip.

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    $\begingroup$ And yes, the unknown hazards do exist. Martian soil contains toxic levels of perchlorates, which weren't discovered until 2008. $\endgroup$
    – Mark
    Commented Aug 12 at 22:20
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    $\begingroup$ This answer is spot-on. People forget that our modern understanding of Mars is actually pretty... modern. Like, late 1990s. Mars Global Surveyor produced the first ever full maps and we didn't have an atmospheric characterization good enough to properly do aerocapture until like 1999. Even with hypothetical extreme funding levels, there are just long travel times and too many unknowns that would stop even a highly risk-tolerant and infinitely funded approach. Even with an overengineered craft, they couldn't just 'wing it' $\endgroup$
    – Dragongeek
    Commented Aug 13 at 6:48
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    $\begingroup$ @Fattie It's also easy to forget how much we used to be able to do without computers. RC cars do not require micro processors at all; the whole control system can be done with traditional circuit boards. Radio guided systems have existed since the 40s, and broadcast video since the 20s. $\endgroup$
    – Nosajimiki
    Commented Aug 14 at 13:55
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    $\begingroup$ @Dragongeek We would send missions to Mars in advance because there was a demand. Part of the Apollo program was the seven Surveyor missions. A critical fact we didn't know about the Moon was the load-bearing capability of the regolith, Surveyor's goal was to characterize that. (In fact, it was not perfectly known and there was "winging": Apollo 11 was ready to blast off if they were wrong and it started sinking. The first photo on the surface was a footpad. It turned out the predictions were conservative and the footpads were over-engineered by being unnecessarily large.) $\endgroup$
    – user71659
    Commented Aug 16 at 21:51
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    $\begingroup$ @user71659 They mathematically took a worst case scenario of perfectly round sand under 1.62 m/s² of gravity and built to that making sure that they were covered for the most unstable sand they could have possibly encountered. What they were surprised by was that the sand was actually razor sharp and ionically charged to cling to and shred their suits. Of all of their best math and conservative estimates of Earth based geology, they could not have predicted what sand on a vacuous planet would be like. $\endgroup$
    – Nosajimiki
    Commented Aug 16 at 22:38
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Could they make the trip using Apollo-era tech? I believe, yes.

I'd hate to be the schmuck who went because Apollo-era tech probably couldn't create the lavish lifestyle environment you see in The Martian. Thus, it would be cramped. Really cramped. Especially given the amount of food, water, and fuel that would need to go with them. But I don't see anything about the tech that intrinsically says "no, can't be done." Thus, yes.

And despite how cramped and ugly life would be like, I expect they'd be beating away people who would want to go with a stick. I'm just sayin'.

The problem isn't the travel. It's the layover.

Here's your biggest problem:

The lowest energy transfer to Mars is a Hohmann transfer orbit, which would involve a roughly 9-month travel time from Earth to Mars, about 500 days (16 mo) at Mars to wait for the transfer window to Earth, and a travel time of about 9 months to return to Earth. This would be a 34-month trip. (Source)

Note that there's a citation request for that 500 day period. But in a sense, the amount of time on the planet doesn't matter. Read on, MacDuff!

It's not the travel time that's the problem. Yes, a plethora of problems could go wrong and since one doesn't have that big lavish ship to comfortably travel in, there's a high risk of problems during that 34-month flight (because the main travel capsule or pod cannot land, IMO, and still be believable for Apollo-era tech. Nor is the landing particularly a problem because, technically, if you launched everything in stages, you could haul an entire Saturn-V rocket and temporary gantry to get you back off the surface.

Why do I say this? Because getting everything you need into space from Earth, where the entire technological and industrial resources of at least one superpower would be available to you, is just a matter of economics (which is a deal-killer, BTW) and time. It's the other direction where you don't have a tech/industry base to draw from that's the problem.

The problem is the 16-months on the planet

Just as it's possible to haul an entire Saturn-V and gantry with you to get you back into space, it's possible to haul all the food and water you need.

And here's where MacDuff comes into it. If you can haul an entire Saturn-V with you, you can haul all the fuel you need to leave when you want, eliminating the need for an energy-conserving Hohmann window. But what would be the fun of that?

But I'm having trouble swallowing that any economically-practical habitat could be hauled with the mission that could keep people alive for 16 months. (And I'd once again hate to be the schmuck who had to stay 16 months in the command capsule.... Computers weren't that good in the 60's.)

If you can haul an entire Saturn-V, couldn't you just haul all the concrete and metal you need? (Of course, if you can haul an entire Saturn-V with you, maybe it doesn't matter if the original command capsule is abandoned... good for that crew member!)

And that's why I'm having trouble with the landing part of this scenario. We've loaded so much mass onto the outbound mission that it's become unreasonable to believe the mission could possibly economically succeed. Citizens were complaining about the cost of the U.S. space program before Apollo even came along. By Apollo 12 the average citizen was done being interested. By Apollo 13 even Congress was wondering about the cost.

Can you imagine the cost of schlepping an entire Saturn-V into space? And then an entire habitat? And everything else you'd need?

Worldbuilding is about simplification

Having said all that, ignore it. Too many worldbuilders, in the quest to be "as realistic as possible," forget not only economics, but forget that worldbuilding is about simplification. Godlike accuracy doesn't make for a better world. It impresses some people, but most find that level of detail boring.

Ignore everything I just said and go build your alternate timeline. It's believable enough.

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    $\begingroup$ At 38% gravity and almost no atmosphere to overcome you only need a fraction of your lander's mass in fuel to get back up to space, not a whole Saturn-V rocket. Taking off from Mars is a bit harder than from the moon, but a lot easier than from Earth. $\endgroup$
    – Nosajimiki
    Commented Aug 12 at 13:23
  • $\begingroup$ @Nosajimiki That's a good point! But they'd still need a vehicle and its fuel to get off the planet and that would all have to be hauled with. So... I'll call it dramatic hyperbole. $\endgroup$
    – JBH
    Commented Aug 12 at 14:48
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    $\begingroup$ Who said anything about spending 16 months on the planet? You could simply do a quick landing to plant a flag and collect samples, and wait out the rest of the layover in orbit, where you already have a habitat. Sure, it's less sexy than spending all that time exploring Mars, but it's much more practical. $\endgroup$
    – Aetol
    Commented Aug 12 at 17:19
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    $\begingroup$ Any reasonable mission is going to be Apollo-style, with the return vehicle waiting in orbit. That means you can pick your balance between "time spent on the surface" and "time in orbit waiting for a transfer window". $\endgroup$
    – Mark
    Commented Aug 12 at 22:17
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    $\begingroup$ @JBH you didn't understand what I said. Yes, Hohmann says they have to wait 16 months before going back. But there's no reason they have to spend those 16 months on the surface of the planet. They can spend that time in orbit, in the same habitat they've been living in for the trip there, after doing a quick dip to the surface. There's no trade-off, you can have a cheap short landing and a cheap efficient return trajectory, as long as you're willing to spend some time twiddling your thumbs in orbit. $\endgroup$
    – Aetol
    Commented Aug 13 at 9:42
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No, the hydrogen for the fuel cells would boil off

The Apollo service module used fuel cells which combined hydrogen and oxygen to produce electrical power for the spacecraft and potable water for the crew. The hydrogen and oxygen were stored as cryogenic liquids in the service module. (The oxygen tank on Apollo 13 was the tank that exploded.)

Even with the best thermal insulation, liquid hydrogen slowly boils away. Either you must vent away the pressure -- slowly emptying the tank -- or the expansion of the gas will violently explode the tank. Therefore, cryogenic hydrogen has a limited storage life. The Space Shuttle also used hydrogen-oxygen fuels cells, and even in the 21st century, Shuttle missions were limited to 30 days duration because of this boil-off problem.

Furthermore, hydrogen gas leaks out even the tiniest of holes. It is very difficult to construct a tank and plumbing to hold gaseous hydrogen for months without leaking. A similar problem is currently happening with the helium pressurization tanks on the Boeing Starliner, causing it to be stranded at the ISS.

The most efficient path to Mars is a Hohmann transfer orbit, which takes 9 months each way, plus 16 months on the surface of Mars, for a total mission of 34 months. Cryogenic hydrogen would not survive that long.

There were solar cells in the Apollo era, but they were horribly inefficient and would not provide enough electricity for the trip. There were plans on paper of a manned Apollo fly-by of Venus, which used solar cells which maybe could have worked because Venus is closer to the sun. (Mars is farther from the sun.) Modern solar cells are much more effective, allowing 21st-century spacecraft to operate with them at/on Mars.

(For the record, I am one of the top answerers for Apollo questions on Space StackExchange.)

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    $\begingroup$ Is that really a deal breaker? If NERVA is on the table as an engine option, then surely that could be tapped for power (or a different small nuclear reactor). And if that isn't viable, RTGs existed. Sure, you'd need a lot of them to support a manned spacecraft, but not an infeasibly large number. For drinking water, you can just carry water - which you probably want to do anyway to provide shielding from solar flares. $\endgroup$
    – asgallant
    Commented Aug 13 at 6:19
  • $\begingroup$ What a great point! $\endgroup$
    – Fattie
    Commented Aug 14 at 12:56
  • $\begingroup$ Just have a James Webb style solar shade for the fuel and have thicker tanks to handle higher pressure. Any fuel burns while in transit can be very low acceleration burns. You could also use a different fuel such as methane for the long transfer instead of H2. $\endgroup$
    – philn
    Commented Aug 14 at 18:32
  • $\begingroup$ @philn That does not help: Hydrogen boils at 20.28 Kelvin - the ambient temperature of space around earth in LEO is 283.32 Kelvin - no ammount of shade can keep the hydrogen cooled: The Webb's shade only managed to get the instuments to 90 Kelvin till the point that they turned on cooling, and the last 83 Kelvin temperature differential needed to be taken off using power. The shaded temperature is still 70 Kelvin too hot to keep hydrogen from boiling. $\endgroup$
    – Trish
    Commented Aug 23 at 12:08
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The Mars Excursion Module was a NASA umbrella proposal for a Mars lander in the sixties. MEM can refer to any number of studies by corporations and spaceflight centers for Mars landers, but usually referred to a combination of a Manned Mars lander, short-stay surface habitat, and Mars ascent stage. Variations on a MEM included spacecraft designs like an uncrewed Mars surface cargo delivery, and there was a MEM lander that combined a communications center, living habitat, and laboratory.

The MEM had a setback when Mariner IV returned data showing how thin the atmosphere actually was, which ruled out many shuttle-type aerodynamic landers.

They thought it was possible at the time. There would be no rescue if things went wrong, but that was also the case for Apollo.

If you think it would be difficult to stay cooped up like that, think of the Fram. This was about 40m by 11m, and was designed to take 17 people on a 5-year journey.

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NASA did actual work on a nuclear powered third stage for the Saturn V rocket. It was for a proposed trip to mars.

I think there was also a study on a one way trip using slightly modified Apollo hardware. You had a single astronaut, travel to Mars, abandon the command module and use a LEM that had no return stage, but more fuel for landing. Explore for a week or until the oxygen / water / food ran out, then open your vizor and die. An informal pool of NASA workers found several volunteers. This was in the days before the internet and I cannot find any records of it.

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Apollo, like the preceding programs, was based on military rocket and ICBM technology mostly existing in the early 1950s. The first successful unmanned Mars lander (Viking 1) was launched a few years after the Apollo program ended. The USSR launched an unsuccessful robotic lander as early as 1962.

A serious engineering evaluation for a possible Mars mission was made starting in 1948 and published in 1952 as a science fiction novel. The author missed a number of issues that would have been discovered if the project was executed, but probably not any show stoppers (they certainly would have accelerated an unmanned Mars mission to evaluate the atmosphere, radiation issues and landing sites). It proposed a fleet of 10 manned and unmanned craft powered by non-cryogenic propellants, and assembled in orbit from 950 launches. A total team of 70 astronauts.

The orginal title was Das Marsprojekt by Wernher Von Braun, with a translation published later. It was republished in English in the mid-2000s as Project Mars, A Technical Tale .

So, it appears there were no major show-stoppers in terms of technology, however the cost would have been (literally) astronomical, and it might have taken a bit longer than estimated, even if the funds were made available immediately.

P.S. for in-flight energy, the author envisioned a solar thermal power plant:

That is a steam boiler. It is heated by the parabolic mirror beside it. The diameter of this mirror is 10.6 meters and it concentrates the solar rays on the generator, permitting steam to be constantly drawn off from it. This steam drives a turbogenerator located within the Central Station, as the hub of Lunetta is called. Thus the whole structure is supplied with 35 kilowatts of electrical energy.

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  • $\begingroup$ Wernher von Braun also had "real" plans for going to Mars, not only a Sci-Fi tale. $\endgroup$
    – Antares
    Commented Aug 17 at 6:05
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No

The primary question for manned landing back then was, and probably still is now, "when and how would we return to Earth?" And it has no valid answer even now, we can't transfer enough resources to ensure a man would return from Mars alive. We barely can transfer enough resources to ensure a colony survival on Moon, even those projects are moving too slowly due to funding reasons and stuff, so no manned Mars even now, unless forced and united, which won't happen in the near future.

Unmanned landing is plausible

After all, take Voyager 1, arm it with some retro-engines and a chute, there you've got a device that's capable of hitting Mars and not getting destroyed in the process. And a probe is not designed to ever return, so why not just leave it there.

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Wernher von Braun would not have agreed.

Not even Wernher von Braun was of the opinion that Apollo-Tech is sufficient for going to Mars. He had ambitious plans for a Mars mission to be conducted right after the moon landing, when "momentum was high". In his schedule he wanted the start to be in Nov/1981 and the landing in 1982. The plan involved continued use of the Saturn V and the development of a nuclear driven "space shuttle" (two of them actually) for six astronauts to reach Mars.

But politics had achieved their goal already with the moon landing and NASA's budget was cut by 10, while the Mars mission would have had needed a doubling of Apollo's budget.

See this article: "The forgotten mission to Mars"

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Frame Challenge: What are you willing to risk in the pursuit of Greatness

Looking at the above - there are two camps of Answers (broadly)

  • it is possible, but difficult
  • It would not be possible

Both Camps have well-reasoned arguments as to why they are correct, but I want to give a slightly Meta-Answer:

If your country has the will to take the risk, then it could be done - but it might not be successfully done.

History is full of moments where people tried to do what was thought impossible and with a combination of Skill, Technology AND copious amounts of Dumb-Luck, they somehow succeeded.

In terms of your question - we know that in this time period we can get into space. We know that we can travel to another heavenly body (the moon). We know that so long as the Government is willing to pump unrestricted money into the R&D and there is people willing to go the extra mile, the Technology will advance rapidly.

Therefore - so long as they are willing to risk it all, I think it is feasible that they would be able to get close enough to try. If it works - great, if not, that is the risk of jumping into the unknown.

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