What if Mars and Venus were habitable?

uk 75

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Well into the 20th Century it was believed that Venus might be a hot humid jungle world and Mars a desert planet with ice caps that melted seasonally bringing life to parts of the planet. Sadly neither view proved true.
But supposing they had been? How would human space exploration have developed after the 1950s to the present day?
Manned expeditions would surely have been mounted by the 1980s to both worlds. Private development by companies and individuals would have been faster as well.
Assuming rivalry between the West and East blocs would these new frontiers have been developed peacefully like the Antarctic or become a source of conflict?
 

Michel Van

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The Old trope of Tropical Venus and Desert Mars ?

Oh man the cold war space race goes into nitro injected overdrive modus
Once the Picture and Data show you could live there (with little Technical help)
USSR and USA will drop the Moon Race and goes for Mars - or Venus Race.

With bigger probes and landers to investigate
NASA get money by Capitol Hill for Nova class booster to bring manned expedition to Mars or Venus
While USSR test N1 so long, until it work for launching manned Mars mission.

but what next ?
Land there put the flag up claim the land for glory of Capitalism or Communism ?
biggest issue will be local wildlife with diseases, predators, poisonous stuff and xenomorphs.
once they got those issues resolved the superpowers could colonise Mars or Venus.

If they have the budget to do it...
 

Orionblamblam

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NASA get money by Capitol Hill for Nova class booster to bring manned expedition to Mars or Venus
Insufficient... especially for Venus. Venus closely approximates Earth in terms of size and mass; launching astronauts from the surface of Venus to Venus orbit through an Earth-like atmosphere would require an Earth-like launch vehicle. So if you land an Apollo capsule on the surface of Venus, you'll need something akin to a Saturn I - with all the launch infrastructure that implies - to get back to Venus orbit. Even much smaller Mars would become far harder to escape if it had an Earth-like atmosphere. Note as well that the Martian atmosphere would be much deeper than Earths due to the lower gravity scale height; stable orbits might start at... who knows? 500 miles?

So orbital manned missions might be possible early on. Manned landings where the men *stay* on the surface might be possible (technically, if not politically) early on. But retrieval of those surface crews might require some substantial technological innovation. Nuclear rockets that turn into nuclear airbreathers for SSTO operations, perhaps.
 

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Are we putting the locals into camps, for their own good, or just buying their land for trinkets, like a used tin of beans?

Logically if we can live there, so can something bigger, better and meaner than us.
 

uk 75

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I tried to leave as broad a range of possibilities as possible. Delighted that some of these have been brought out above.
 

publiusr

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Venus is where something like Bono's huge saucer would shine. Sea Dragons to top it off for insertion. It would have a whole Titan-Gemini erector for a spine...the saucer now a pad. Gemini docks with a Sea Dragon launched mega-Agena to be pushed home. Mars might be tougher actually.
 

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Venus is where something like Bono's huge saucer would shine.

The one he designed simply to show that it was not a good design? Yeah, no, a saucer would be worse than a rationally designed launch vehicle... especially for launch through a meaningful atmosphere.
 

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Are we putting the locals into camps, for their own good, or just buying their land for trinkets, like a used tin of beans?

Buying them off with beads. In fact, a single bead will do the trick.

MartianBead.png
 

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You want something with a wide footprint to serve as a pad in those dino infested swamps right? This is all kitsch—for fun.

You got your saucer...can use stock Gemini footage with a long necked sauropod peeking into the capsule with a matte of the saucer at the screen bottom covering real pad handrails. Here, the choice was for filming as much as anything. Now, wasn't a scaled up Dyna Soar looked at for Mars return had the atmosphere been a little thicker?
 
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So the obvious problem is how and the logical answer is that like Earth they both have sufficiently large heavy element cores to stay molten and generating strong magnetic fields.

The risk is intelligent life evolving which don't just make it problematic to exploit these planets. But could potentially contest Humanity for control of Earth and the Solar System.

This contest and it's threat could dramatically alter our politics.
 

Dilandu

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Insufficient data. Are these worlds actually loaded with life... and if so, does that life come equipped with horrible diseases that melt human flesh and wipe out the initial expeditions within hours of landing?
Low probability. Unless we implement panspermia, the organic on all three planets would most likely not be compatible. Speaking specifically about dangerous pathogens:

* Viruses - zero danger. Viruses are very-very-very firmly linked to living cells. Viruses aren't even alive outside living cells. They could became active only by infiltrating living cell and using its resources to reproduce viruses. And it's pretty obvious, that alien virus would have absolutely no idea what to do with Earth cell, simply because its genetic code is absolutely incompatible with virus own.

* Bacteria - low danger. Bacteria have their own metabolism, so they theoretically could be somewhat adapted to survive in alien organism. But... they simply wouldn't be efficient here. For alien bacteria, Earth organism would be a set of extreme conditions and very hard-to-digest food at best; deadly conditions and poisonous food at worst. Earth own bacteria - MUCH better suited to survive in Earth organisms - would gave alien ones a Very Hostile Welcome also.

* Fungus, mold - actually, those could represent some danger. Those organism are known for the ability to survive in extreme conditions, they could digest quite a lot, so... it's not exactly impossible for alien mold to cause SOME problems for Earth organisms. Still, it would most likely be a very reluctant infestation; Earth organisms still very far from what alien mold adapted to.
 

Dilandu

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So if you land an Apollo capsule on the surface of Venus, you'll need something akin to a Saturn I - with all the launch infrastructure that implies - to get back to Venus orbit.
Actually no, you could get out with much smaller, solid-fuel (or storable-fuel) rocket, dropped in launch container. Just make the return capsule REALLY light. After all, its strictly Venus-to-Orbit craft; all it does need is to launch from Venus and dock with orbiting Earth return ship. V-t-O capsule does not need to have thermal protection (it would not need to re-entry atmosphere), does not need to have prolonged life support (we could safely get away with crew being in spacesuits all the return flight).

Basically, look at something like Space Cruiser/STAR:

1640994049042.png

1640994124179.png

Threw away all thermal titles, lifting surfaces, most of the fuel. Leave only the basic: structure, life support, ACS and minimal propulsion. You could fit it in the one ton of payload, or even less. My IMHO, a 500-kg return capsule is perfectly possible. And 500 kg to low Venusian orbit is within the Minotaur-I rocket capabilities.
 

Orionblamblam

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Insufficient data. Are these worlds actually loaded with life... and if so, does that life come equipped with horrible diseases that melt human flesh and wipe out the initial expeditions within hours of landing?
Low probability.
Yes, but... Venus and Mars being swamp-covered and life bearing are *zero* probability. So once you establish that impossibility (since it is verifiably *not* true that either planet is actually like that), then low probability events suddenly become quite important to consider. Beyond horrifying diseases, does one or the other of these planets grow a crop of liftwood? Does NASA get to Mars not with nuclear rockets, but with ether propellers? Do you need to worry about flatcats eating up the food stores on your family spaceship? Will the womenfolk of Earth have to worry about losing all their menfolk to the Venusian Amazons and their non-stop Snu Snu?

Inquiring minds want to know.
 

Orionblamblam

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My IMHO, a 500-kg return capsule is perfectly possible. And 500 kg to low Venusian orbit is within the Minotaur-I rocket capabilities.

You'd still need to land a Minotaur... and whatever you need to *launch* a Minotaur. Presumably you'd land the rocket with some sort of minimal launch complex, and somewhere nearby a fuel processing facility to turn the abundant local swamp water and swamp gas into, say, liquid oxygen and liquid methane. But you'd also have to land a batallion of Cyberdyne Systems hunter-killer drones to hold off the attacks from the pseudotyrannosaurs and the lizardmen.
 

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Venus and Mars being swamp-covered and life bearing are *zero* probability
Not exactly for Venus; its not impossible to imagine conditions in which Venus might be more Earth-like.
True... but the fact is that Venus is *not* Earth-like, and thus the probability of it being Earth like is definitionally zero.

Any change to the timeline that allows for Venus to be Earth-like *today* would necessarily require a *major* change in events. Tinker with the rotation of Venus somehow, give it a 48-hour day and a Luna-like moon, perhaps. And we've seen that whenever Q or Trelane does this sort of thing, there are always unanticipated side effects. Venus having an ecosystem leads to astrology actually working, say.
 

Dilandu

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You'd still need to land a Minotaur... and whatever you need to *launch* a Minotaur. Presumably you'd land the rocket with some sort of minimal launch complex, and somewhere nearby a fuel processing facility to turn the abundant local swamp water and swamp gas into, say, liquid oxygen and liquid methane. But you'd also have to land a batallion of Cyberdyne Systems hunter-killer drones to hold off the attacks from the pseudotyrannosaurs and the lizardmen.
Sigh. Americans and their inability to make a good ICBM. Just put a fully-fueled solid or storable liquid rocket into the sealed container with dry nitrogen atmosphere - like Soviet ICBM's were stored - provide the container with heat shield on bottom end, parachutes and inflatable flotation baloons on the top. Drop the container onto the Venus, aiming into big enough lake. The water would both make landing softer, and solve all problem with rightening the rocket; it would just float perfectly vertically, with only top part of container above the water. Provide your astronauts with inflatable boats, so they could reach the reutrn rocket in the lake.
 

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You'd still need to land a Minotaur... and whatever you need to *launch* a Minotaur. Presumably you'd land the rocket with some sort of minimal launch complex, and somewhere nearby a fuel processing facility to turn the abundant local swamp water and swamp gas into, say, liquid oxygen and liquid methane. But you'd also have to land a batallion of Cyberdyne Systems hunter-killer drones to hold off the attacks from the pseudotyrannosaurs and the lizardmen.
Sigh. Americans and their inability to make a good ICBM. Just put a fully-fueled solid or storable liquid rocket into the sealed container with dry nitrogen atmosphere - like Soviet ICBM's were stored - provide the container with heat shield on bottom end, parachutes and inflatable flotation baloons on the top. Drop the container onto the Venus, aiming into big enough lake. The water would both make landing softer, and solve all problem with rightening the rocket; it would just float perfectly vertically, with only top part of container above the water. Provide your astronauts with inflatable boats, so they could reach the reutrn rocket in the lake.
That's lame. For starters, a solid fuel rocket would cost a *lot* more to launch and deal with than an empty liquid rocket. Second, when you've launched your solid, what have you left on the surface? Nothing of consequence. But a liquid system would leave behind the fuel processing facility, ready for the next rocket and the colonists, miners, scientists, mercs and imperial administrators that will make use of it.

Besides: who would be insane enough to go paddling across Lake Sea Monster with its krackens and pliosaurs? OK, sure, some Russians lubed up on Vodka and some American millenials too busy takign selfies to notice the fangs, maybe, but they still wouldn't make it a third of the way there before they get snarfed down by the horrible abominations lurking in that fetid pond.
 

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Well the Parties Entreated at the Mountain of Vermillion Cloud obviously see those horrible creatures on the third planet as just awful and in need of orbital bombardment with nukes.

After much communication with The Union of Barsoom, the powers of the fourth planet agree.
 

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Swap Mars and Venus's orbits, Mars is where Venus is and vice versa. For extra super fun... say at some point in the past "Venus" managed to nab Europa as a moon. So now you have a near twin of Earth with a moon that has a nice twist.

Earth telescope would see water and cloud pretty early on.. it would spur development earlier.
 

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Insufficient data. Are these worlds actually loaded with life... and if so, does that life come equipped with horrible diseases that melt human flesh and wipe out the initial expeditions within hours of landing?
Low probability.
Yes, but... Venus and Mars being swamp-covered and life bearing are *zero* probability. So once you establish that impossibility (since it is verifiably *not* true that either planet is actually like that), then low probability events suddenly become quite important to consider. Beyond horrifying diseases, does one or the other of these planets grow a crop of liftwood? Does NASA get to Mars not with nuclear rockets, but with ether propellers?
D894D026-87BB-4FB1-BE52-DB557B694CD3.jpeg
 

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According to the "canon" Venus was to be a wet tropical planet (La Réunion Island / Vietnam written large) when Mars was to be pretty dry and only saved by irrigation canals (think Middleast / Northern Africa / Egypt except without the three monotheist religions lunacies and fanatics)

Swap Venus and Earth rocky bodies: Venus is 20% lighter and 10% smaller in radius. Let the Venusians struggle with a goddam planet just a little too big for hydrolox SSTOs, while we enjoy an orbital velocity 10% lower.

Of course by this metric Mars is a SSTO pornfest.

Shame Venus didn't had a Moon, even a Mars-like potato.

Incidentally, Venus seems to be a dreamland for Zeppelins, what's not to like ?
 

Dilandu

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And the nation that goes to that effort will conquer Venus, not just land there.
Unless it achieve landing & returning first, it would conquer nothing but excessive spending. To use in situ resources, the resources in question must be investigated. What's the point of sending costly hydrogen-producing plant on alt-Ventus, only to find out that due to unnoticed previously microscopic aglae (which automatic probes missed) its pumping system get clogged half an hour after launch?

The first manned step should be a weeks/months long mission to make complex investigation; and such mission would require return craft that is reliable firstly, everything else secondly. In situ resources use could be implemented of following mission, after it would became clear how to implement such resources.
 

Orionblamblam

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And the nation that goes to that effort will conquer Venus, not just land there.
Unless it achieve landing & returning first, it would conquer nothing but excessive spending. To use in situ resources, the resources in question must be investigated. What's the point of sending costly hydrogen-producing plant on alt-Ventus, only to find out that due to unnoticed previously microscopic aglae (which automatic probes missed) its pumping system get clogged half an hour after launch?

The first manned step should be a weeks/months long mission to make complex investigation; and such mission would require return craft that is reliable firstly, everything else secondly. In situ resources use could be implemented of following mission, after it would became clear how to implement such resources.
Why would automatic probes miss this? The in situ plants would be sent well in advance of the human mission. First small subscale facilities on probes just to see if it works; then larger facilities to support sample return missions, then larger still facilities in preparation for manned missions.
 

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Well into the 20th Century it was believed that Venus might be a hot humid jungle world and Mars a desert planet with ice caps that melted seasonally bringing life to parts of the planet. Sadly neither view proved true.
But supposing they had been? How would human space exploration have developed after the 1950s to the present day?
Manned expeditions would surely have been mounted by the 1980s to both worlds. Private development by companies and individuals would have been faster as well.
Assuming rivalry between the West and East blocs would these new frontiers have been developed peacefully like the Antarctic or become a source of conflict?
It's an interesting idea, Colon was looking for an alternative route to China because he knew China existed.
 

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According to the classical theory of the golden age of science fiction, Venus should be a primitive world in a stage of development equivalent to the Jurassic and Mars should be inhabited by an intelligent race much more evolved than ours and with technology advanced enough to prevent colonization, and even landing.
 

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Dilandu

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Why would automatic probes miss this? The in situ plants would be sent well in advance of the human mission. First small subscale facilities on probes just to see if it works; then larger facilities to support sample return missions, then larger still facilities in preparation for manned missions.
Because automatic probes aren't exactly good in finding something they do NOT expect to find. Testing for the expected? Yes, that's good. Noticing something not expected? Probes utterly fail here.
 

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Why would automatic probes miss this? The in situ plants would be sent well in advance of the human mission. First small subscale facilities on probes just to see if it works; then larger facilities to support sample return missions, then larger still facilities in preparation for manned missions.
Because automatic probes aren't exactly good in finding something they do NOT expect to find. Testing for the expected? Yes, that's good. Noticing something not expected? Probes utterly fail here.
And so when the automated fuel processor starts up, it'll either work or it won't. If it fails, there are no astronauts relying on it.
 

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Tangential: Though Mercury is very hot, IIRC still not enough to burn off its crust. It's much as you'd expect for a glancing mega-collision's loser. As if Earth_0.1's 'Theia' side-swiped rather than merged, well, 'merged', if you count vast debris ring that accreted to Earth_1.0 plus Moon. Had Earth been less massive, much may have been lost.

So where did Mercury's crust go ??
Venus ? Clonking rotation in passing ? But would have, at very least, blown atmosphere off tangent, if not hemisphere, if not entire planet, then Solar Wind would have dispersed it. Is that what happened to Mars ??

That aside, there's some serious peculiarities about Venus. IIRC, the 'overturn' hypothesis has not been entirely falsified. Idea is that Venus, lacking water, lacks 'steady' plate tectonics. Instead, heat builds beneath crust until near-global 'flood basalt' event, with vast slabs of crust subsiding, and a lot of gas release. Taking atmosphere from merely horrid to truly hellish, such we're seeing aftermath of such...
{Sigh... }

All good fun, but I'm sorry that comet missed Mars a few years back. Would have been interesting...
 

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All good fun, but I'm sorry that comet missed Mars a few years back. Would have been interesting...

That would have been close to an instant terraforming event. Had humanity been on the ball... *if* that comet had hit, we could have leveraged that to a permanent terraforming, at least to some useful degree.

Sigh.

Every now and then I think back to those halcyon days when 2004 MN4 Apophis looked like a serious threat for impact with Earth in 2036. Apophis is big enough that an impact is likely to be civilization-ending, if not extinction level; but small enough that humanity could have nudged it off course with a series of megaton-yield pulse units derived from Orion studies. And the timeframe was *perfect,* thirty years to deal with it. Had it remained a threat, mankind could have either developed a truly useful space economy filled with nukes and nuclear reactors, or given up the ghost and gone the way of failed cultures like the Inca or Greenland Norse.

Sigh.
 

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If they have the budget to do it...

This is the big problem, especially with Venus. To get back home you not only have to climb out of Venus' gravity well, but the sun's also. You would somehow have to create the infrastructure to at least build from scratch from local materials to at least put payloads in Venus' orbit. The ability to refuel the Earth-Venus shuttles would be needed also.
 

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If they have the budget to do it...

This is the big problem, especially with Venus. To get back home you not only have to climb out of Venus' gravity well, but the sun's also. You would somehow have to create the infrastructure to at least build from scratch from local materials to at least put payloads in Venus' orbit. The ability to refuel the Earth-Venus shuttles would be needed also.

Any reasonably conceivable near-term technology - apart from Orion - would include large quantities of cryogenic propellants. LOX/LH2 or LH2/nuclear, you're going to have giant dewars filled with cryogens in orbit not just around a warm planet, but closer to a hot star. Obviously considerable efforts will be made to reduce boiloff, doubtless including sun shades akin to those used by the Webb telescope. It would of course be far better to be in a relatively high orbit around Venus, to limit the heating from the planet itself, since the ship will almost certainly maintain an orientation to the sun that minimizes solar insolation.

But realistically, something that any meaningful exploration of the planet will need is fuel shipped up from the surface to replenish the vast quantities lost on the trip to Venus and while in orbit. Perhaps the approach to use will be to use ROMBUS or NEXUS-like SSTO vehicles as boosters to get to Venus... and once at Venus, use those SSTOs as first landers, lowering the initial equipment for bases and forts, and then to tank them back up and use them as surface-to-orbit shuttles. The amount of payload going uphill will be small, likely little more than the astronaut crew, some geological samples, some flora and fauna, and some stowaway Amazons who have of course fallen in love with the hunky Captain and first officer. So the bulk of the up-mass will be LOX/LH2 used to tank up the orbital ship for the return to Earth.

After a series of unmanned probes have demonstrated the various technologies, and an orbital-only manned mission remotely oversees the initial setup of the rudiments of a base on the surface, the first real manned mission would doubtless be a fairly vast armada... perhaps half a dozen ships and landers, a hundred crewmen.
 

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According to the classical theory of the golden age of science fiction, Venus should be a primitive world in a stage of development equivalent to the Jurassic and Mars should be inhabited by an intelligent race much more evolved than ours and with technology advanced enough to prevent colonization, and even landing.
Even then, folks had Mars as a dying, Ceti Alpha V type world….the advances not being enough…but their technological secrets would be of great use to Earth. Our gravity and that of Venus too much for them.
 

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