What is the earliest point in history for a viable space program?

[xxmagex]

I was wondering and I thought I would ask the forum as I'm sure there are much smarter people than me here. What is the earliest point in history for a viable space program, a program able to get men and equipment into orbit? In OTL, it was the late 1950s, could it have been earlier?

I personally don't think we can get too much earlier, maybe the mid to late 1940s basing off the German and British programs, than OTL, but I was wondering if I was wrong.

Also, would it have to be conventionally rocket based? By that, I mean could it be an offshot of something like a space plane that flys into orbit. Perhaps something like a Air Launch to Orbit system? Or some other method I haven't even thought of.

What are the thoughts of the forum?

 

[DougM]

MAYBE you can move it up 5 to 7 years, but it is going to have huge issues.
And it all depends on how you define “space program”
the late 40s and early 50 to late 50s saw huge developments in Electronics and material science and structural/aerodynamic engineering as well as a lot of test programs to undertake various conditions such as supersonic flight and what have you.
It also saw developments in manufacturing and machining that were ul important. As the saying goes ”you can’t railroad until it is time to railroad”. So you need a lot of things to come together to make a truly functional space program.

If you mean just sticking a radio transmitter up past the Kerman line, Then that could be done with a bigger badder next generation of the V-2 (basically the multi stage version you always hear about). So that could be done in the late 40s

If you want an orbit such a s Sputnik then that is harder. You could scrape the tech together if you tossed a ton of money at it probably in 52 ish. But you won’t get that money as there is no reason for a government to build that rocket.
Early rockets and thus the earlier space programs are built on the tech used ultimately for ICBMs if mot actually using an ICBM. But until the tech allows you to make a nuke small enough to fit on an ICBM then there is not much point in building the ICBM as they are to expensive and inaccurate to use with conventional weapons.

Now if you want to actually put a man in space. Then you are looking at probably 57-60. You will note that the bigger the goal the close to original timeline it gets as you need more and more systems and technologies and skills and knowledge to ALL be at a level if maturity that will allow for it,
You can built a bigger V-2 without much new tech but a rocket to put a man in orbit and return them requires add tech. And you can only rush that so fast.
I mean theoretically if you got every man woman and child working on developing the tech starting in 1946 and you bankrupt the world you could punch the moon landings ahead by 10 years or whatever. But in any world that is the same as our give or take through WW2 and that has to live in a real world with the cost of rebuilding and everything else that a government has to pay for then you just can’t advance ALL the areas of science and knowledge that are needed all that much faster then we did.
Yes the US didn’t exactly press hard on developing rockets after WW2 but there was good reasons for that.

So if you want a moon landing you are looking at 65-67 soonest you will get. Just for example the ”computer” Tech in the capsule and the lander were bleeding edge in 68 when they were being built but they barely where good enough to get the job done.

So in order to get more then a year or two you have to advance SO many things you just can’t do it.
You need the materials for the rocket engines, the heat shields, the structure, the fuel tanks, the space suits etc,
You need the advances in chem and such for the fuels.
You need to improve batteries/power units, and then you need to advance whatever you are running with the electricity so they don’t suck to much power for the batteries/power units you have,
You need to improve electronics in general and computer specifically to not just fit in said rockets but to do the math involved in the orbits and the design calculations once you move past slide rulers and such. Oh and you need to improve (all but invent) programming and data entry and data storage and debugging etc.
While you are developing the above you have to run experiments to figure out supersonic flight, how much pressure and gees and what have you a human can take, how to build a structure for the rocket and capsule that won’t fall apart under the load (once you can figure out what that load is)
Now once you have all your materials and you knowledge to design things you need to figure out how to build them. And that is a whole new can of worms.

So you don’t just need to advance “the space program” by 5 years (or whatever) you need to advance just about EVERYTHING by 5 years EACH. So you are looking at probably 10 of thousands of many years worth of work (or a lot more )
Heck even medicine has to advance so we can understand how to keep the astronauts alive and we have to advance food prep to feed them. Etc etc etc etc.

So yes you could cut out the slow time when the US was not pushing vary hard/fast. But you have to advance the rest of the tech as well that was being developed during those slow years.

So
TLDR
Sub orbital rocket, late 40s,
Satalite: early 50s (like Sputnik)
Man in space: late 60s
Man on moon 67 or so.
trouble is getting anyone to pay for this as it will be more expensive as you have to develop things to build the program from.

 

[Mad Bad Rabbit]

Into orbit alive, and back alive?

 

[Blue cat]

MAYBE you can move it up 5 to 7 years, but it is going to have huge issues.
And it all depends on how you define “space program”
the late 40s and early 50 to late 50s saw huge developments in Electronics and material science and structural/aerodynamic engineering as well as a lot of test programs to undertake various conditions such as supersonic flight and what have you.
It also saw developments in manufacturing and machining that were ul important. As the saying goes ”you can’t railroad until it is time to railroad”. So you need a lot of things to come together to make a truly functional space program.

If you mean just sticking a radio transmitter up past the Kerman line, Then that could be done with a bigger badder next generation of the V-2 (basically the multi stage version you always hear about). So that could be done in the late 40s

If you want an orbit such a s Sputnik then that is harder. You could scrape the tech together if you tossed a ton of money at it probably in 52 ish. But you won’t get that money as there is no reason for a government to build that rocket.
Early rockets and thus the earlier space programs are built on the tech used ultimately for ICBMs if mot actually using an ICBM. But until the tech allows you to make a nuke small enough to fit on an ICBM then there is not much point in building the ICBM as they are to expensive and inaccurate to use with conventional weapons.

Now if you want to actually put a man in space. Then you are looking at probably 57-60. You will note that the bigger the goal the close to original timeline it gets as you need more and more systems and technologies and skills and knowledge to ALL be at a level if maturity that will allow for it,
You can built a bigger V-2 without much new tech but a rocket to put a man in orbit and return them requires add tech. And you can only rush that so fast.
I mean theoretically if you got every man woman and child working on developing the tech starting in 1946 and you bankrupt the world you could punch the moon landings ahead by 10 years or whatever. But in any world that is the same as our give or take through WW2 and that has to live in a real world with the cost of rebuilding and everything else that a government has to pay for then you just can’t advance ALL the areas of science and knowledge that are needed all that much faster then we did.
Yes the US didn’t exactly press hard on developing rockets after WW2 but there was good reasons for that.

So if you want a moon landing you are looking at 65-67 soonest you will get. Just for example the ”computer” Tech in the capsule and the lander were bleeding edge in 68 when they were being built but they barely where good enough to get the job done.

So in order to get more then a year or two you have to advance SO many things you just can’t do it.
You need the materials for the rocket engines, the heat shields, the structure, the fuel tanks, the space suits etc,
You need the advances in chem and such for the fuels.
You need to improve batteries/power units, and then you need to advance whatever you are running with the electricity so they don’t suck to much power for the batteries/power units you have,
You need to improve electronics in general and computer specifically to not just fit in said rockets but to do the math involved in the orbits and the design calculations once you move past slide rulers and such. Oh and you need to improve (all but invent) programming and data entry and data storage and debugging etc.
While you are developing the above you have to run experiments to figure out supersonic flight, how much pressure and gees and what have you a human can take, how to build a structure for the rocket and capsule that won’t fall apart under the load (once you can figure out what that load is)
Now once you have all your materials and you knowledge to design things you need to figure out how to build them. And that is a whole new can of worms.

So you don’t just need to advance “the space program” by 5 years (or whatever) you need to advance just about EVERYTHING by 5 years EACH. So you are looking at probably 10 of thousands of many years worth of work (or a lot more )
Heck even medicine has to advance so we can understand how to keep the astronauts alive and we have to advance food prep to feed them. Etc etc etc etc.

So yes you could cut out the slow time when the US was not pushing vary hard/fast. But you have to advance the rest of the tech as well that was being developed during those slow years.

So
TLDR
Sub orbital rocket, late 40s,
Satalite: early 50s (like Sputnik)
Man in space: late 60s
Man on moon 67 or so.
trouble is getting anyone to pay for this as it will be more expensive as you have to develop things to build the program from.

I tend to agree.

Perhaps a gun based system (perhaps with a simple solid fuel rocket booster as well ?)might have been able to put an object briefly into space shortly after WW1 ? But I doubt the electronics of the day would have been adequate to return any data from such a flight or even provide for tracking data to establish how far into space the object travelled ?

 

[Gunnarnz]

There was a book called "King David's Spaceship", in which a society with early 1900s tech (spark gap transmitters, clockwork mechanisms with punched metal tape controlling them, etc) managed to launch a crewed craft into orbit. The crew was injured, but survived. The propulsive agent was explosive shells, fired from the craft by a rapid-fire cannon - a sort of variant of an Orion-type drive. Sure, it's sci-fi, and so not to be taken as gospel, but it seems at least theoretically possible.

 

[Garrison]

There was a book called "King David's Spaceship", in which a society with early 1900s tech (spark gap transmitters, clockwork mechanisms with punched metal tape controlling them, etc) managed to launch a crewed craft into orbit. The crew was injured, but survived. The propulsive agent was explosive shells, fired from the craft by a rapid-fire cannon - a sort of variant of an Orion-type drive. Sure, it's sci-fi, and so not to be taken as gospel, but it seems at least theoretically possible.

That was against the background of an interstellar civilization and they were able to access an extensive history of spaceflight to come up with a solution. Even if people took the work of Goddard seriously in the 1920s and someone was willing to put in the funding, and I'm thinking of Howard Hughes rather than the government, I don't think you could shave off more than a few years so maybe the mid to late 1940s.

 

[NHBL]

I have an ongoing timeline based on a SERIOUS perceived need to deflect incoming asteroids, with a POD of 1876 <sic>. It's in ASB because it involves a geological POD--a meteor strike--but I'm trying to keep it plausible. A meteor blasts out a hole a couple of miles across in New Hampshire's White Mountains. Naturally, this puts shooting stars and Great Meteors of 1783 and 1860 in a different perspective. It also shows people what to look for to find evidence of a meteor, as the geology of the White Mountains before and after is studied.
Skywatch is established, and serious investigation of reaching extreme altitudes are started, from rockets to sling launchers to electro-gravitic launchers and gravity shielding materials.
As of 1879, space is a long ways away, but discoveries are being made, while the rest of the world is mostly amused at America's obsession with the sky.
Heavier than air flight may well come by the 1880's, , though I can't see anyone getting into orbit and returning alive until the 1940's or later. (Suborbital, possibly.)
If interested, check out Reach For the Skies: A Space Mad USA in 1876

 

[Arkenfolm]

I have an ongoing timeline based on a SERIOUS perceived need to deflect incoming asteroids, with a POD of 1876 <sic>. It's in ASB because it involves a geological POD--a meteor strike--but I'm trying to keep it plausible. A meteor blasts out a hole a couple of miles across in New Hampshire's White Mountains. Naturally, this puts shooting stars and Great Meteors of 1783 and 1860 in a different perspective. It also shows people what to look for to find evidence of a meteor, as the geology of the White Mountains before and after is studied.
Skywatch is established, and serious investigation of reaching extreme altitudes are started, from rockets to sling launchers to electro-gravitic launchers and gravity shielding materials.
As of 1879, space is a long ways away, but discoveries are being made, while the rest of the world is mostly amused at America's obsession with the sky.
Heavier than air flight may well come by the 1880's, , though I can't see anyone getting into orbit and returning alive until the 1940's or later. (Suborbital, possibly.)
If interested, check out Reach For the Skies: A Space Mad USA in 1876

I've never read your TL (maybe I should since I'm always intrigued by early spaceflight/air travel), but this could have been reality in regards to Tunguska. Had Russia--or a different nation like modernized Golden Horde--extensively settled Siberia, then such a disaster might have killed/injured more than a few reindeer herders and been an impetus for astronomy and rocketry. There is also a chance for a more developed China to join this should the 1490 disaster in Qingyang recorded in History of Ming be interpreted as an asteroid impact (or some very early modernizing China interpreting it as such) meaning the Chinese government strives to have it never happen again.

I believe there is a potential for early rockets based on late 19th century chemistry but at that date space guns are a perfectly reasonable solution and one which the military will love since it involves making big artillery. If done right you'll have a 1930s space race driven by national security concerns meaning satellites and space-based wunderwaffen plus ASAT warfare. The counter is putting more and more resilient satellites in space meaning more launch capacity which at that early date means something like Sea Dragon or early reusable rockets or maybe some sort of air launched concept via giant airships.

 

[Nell_Lucifer]

It is quite hard to say when was the earliest point in time that a space program could have been viable, it would require a good amount of digging through specialized books about the history of metallurgy, chemistry, machining, mechanical engineering and electronics as without knowing what was available then it would be a pointless endeavor.

Though, I would say if the 1908 meteorite hit Belgium and not Siberia then you could see man reaching space much earlier, in the 1920s I would say, depending on how aggressive the program/s is/are or how generous the funding is.

 

[Polish Eagle]

In general, you really can't pull off space travel without the technical toolbox of the mid 20th century. Lightweight, high-temperature alloys, a chemical engineering industry to make propellant, at least some kind of computing ability for rocket guidance (though maybe you could replace the last one with stick-and-pedals controls), the ability to make airtight seals on the spacecraft, CO2 scrubbing, etc.

You could postulate big divergences in history so that these tools are available in the 19th century or earlier (the old steam-powered Roman Empire or Song Dynasty China tropes), but I don't think you can pull off clockpunk spaceships.

 

[Rhymehouse]

With minimal butterflies, you could pull it off in the 1940s. With major butterflies, you could pull it off during the 1800s, but that would require a much more advanced timeline with many different PODs all the way back in medieval times.

 

[NHBL]

I've never read your TL (maybe I should since I'm always intrigued by early spaceflight/air travel), but this could have been reality in regards to Tunguska. Had Russia--or a different nation like modernized Golden Horde--extensively settled Siberia, then such a disaster might have killed/injured more than a few reindeer herders and been an impetus for astronomy and rocketry. There is also a chance for a more developed China to join this should the 1490 disaster in Qingyang recorded in History of Ming be interpreted as an asteroid impact (or some very early modernizing China interpreting it as such) meaning the Chinese government strives to have it never happen again.

I believe there is a potential for early rockets based on late 19th century chemistry but at that date space guns are a perfectly reasonable solution and one which the military will love since it involves making big artillery. If done right you'll have a 1930s space race driven by national security concerns meaning satellites and space-based wunderwaffen plus ASAT warfare. The counter is putting more and more resilient satellites in space meaning more launch capacity which at that early date means something like Sea Dragon or early reusable rockets or maybe some sort of air launched concept via giant airships.

I like to think you will enjoy it--rockets, shooting, and you can't make just one change--the butterflies are flapping, enough so that Reconstruction isn't over everywhere in 1879, and there's serious changes in technology, women's suffrage, and other areas. (No, no one's flying heavier than air craft at that time.)

In general, you really can't pull off space travel without the technical toolbox of the mid 20th century. Lightweight, high-temperature alloys, a chemical engineering industry to make propellant, at least some kind of computing ability for rocket guidance (though maybe you could replace the last one with stick-and-pedals controls), the ability to make airtight seals on the spacecraft, CO2 scrubbing, etc.

You could postulate big divergences in history so that these tools are available in the 19th century or earlier (the old steam-powered Roman Empire or Song Dynasty China tropes), but I don't think you can pull off clockpunk spaceships.

I agree there. Clockpunk rockets that reach space, or perhaps eventually reach orbit--possible. Come back in one piece, or carry a person to orbit--less likely.

 

[FellowTraveller5]

In general, you really can't pull off space travel without the technical toolbox of the mid 20th century. Lightweight, high-temperature alloys, a chemical engineering industry to make propellant, at least some kind of computing ability for rocket guidance (though maybe you could replace the last one with stick-and-pedals controls), the ability to make airtight seals on the spacecraft, CO2 scrubbing, etc.

There is quite a bit of winking and nodding going on in "Reach for the Skies" over the Navy's place in running Skywatch. Yeah, sure, it's all about developing spacecraft technologies (and the applicability of said technologies to torpedoes and submarines is purely coincidental). Big rockets are still a ways off, but the bazooka...

 

[Peg Leg Pom]

Serious experiments with liquid fuelled rockets didn't begin until the 1930's with initial work done in the 1920's. High energy solid fuels didn't come to be until the late 1940's. It's hard to see how given that the space programs can be greatly advanced by more than five years with that timeline and without military involvement due to the need for missiles it would be set back 15 - 20 years. I'd personally say the space programs did happen at the earliest feasible time.

 

[Dorknought]

NASA can trace its origins back to1915 (NACA)

 

[xxmagex]

I’ve been pondering this question. Originally, I was thinking someone like Howard Hughes, an early Elon Musk, was the solution. However, the sheer breadth of what would need to be done makes that scenario unlikely. Then it hit me.

Robert Heinlein.

Allow me to explain. Robert Heinlein was a graduate from the Naval Academy at Annapolis in the late 1920s and early 1930s. One of his first assignments was as a radio technician on the USS Lexington in 1931. Back then, that was the cutting edge of technology. I read a biography of him years ago where he was talking about a situation where they were trying to contact another ship/plane and they were unable to do so. Heinlein was talking about how it would have helped if there had been something available that they could bounce the signal off to increase the distance. The thought struck me that he was describing using a satellite to increase the range of radio communications.

In 1931, the commander of the USS Lexington, one of the first aircraft carriers that the United States Navy had, was one Ernest King.

The name may sound familiar to you as he was appointed Chief of Naval Operations for the US Navy after the Pearl Harbor attack and commanded the US Navy through World War Two.

There seems to have been some connection between Heinlein and King. I’ve seen one reference to Heinlein dating one of King’s daughters, no doubt a daunting task considering King’s well-known temper. Also, Heinlein was routinely interviewed by historians about his time with King.

Let us say that the satellite idea took firmer hold in Heinlein’s mind at the time and he was vocal about it, to the point he may have mentioned it to King.

Fast forward ten years to right after Pearl Harbor. King is now in command of the US Navy with all the resources that go with that. In the back of his head, he remembers Heinlein’s comment about increasing radio range by bouncing the signal off these satellites he mentioned. There may be something to this and since the US if fighting a global war, increasing the range and speed of communication is something that would help the war effort. He reaches out to Heinlein.

By this time, Heinlein had been out of the navy ten years due to health reasons. In OTL he worked on aerospace R&D with other science fiction writers and engineers. IIRC, it was mostly on plane performance and the like.

However, in this TL, King tells them to work on something to increase the range of communications by bouncing the signal off these satellites.

The research leads to Robert Goddard’s work. Goddard was not unknown, the New York Times had written about him in the 1920s. Of course, the Times was mocking his work, but it was in the public eye then. Other media had also written about rocketry used to place things into space. I think the Smithsonian had also been involved in the public discussion.

Rocketry was not unknown at the time. So, it follows that this research program looks at rocketry as a method to get the satellites into orbit. Does Goddard cooperate? Maybe, maybe not. He was a difficult personality from what I can gather, and I’ve read some history saying that he was concerned about military applications of his work. However, this is war and they’re not actually asking him to drop bombs on people, this is to get something into orbit for what he can justify to himself. So, let’s say he does cooperate.

So, we have a functioning rocket program dedicated to getting things into orbit with support of the Navy. I expect there will be some progress.

I don’t think it will be spectacular progress, we’re not going to leapfrog in front of the Germans, but when the news of the V2 breaks, more resources are made available to them.

Are they going to get a satellite into orbit before the war is over? I doubt it. They probably can get a rocket out of the atmosphere and are making progress. The war ends and the team gets access to the stuff the Germans had.

Now, the question here becomes does the program continue. At this point, I think the advantage of what they are doing would be clear to the Navy brass and they would want the research to continue. However, the civilian leadership is determined to cut costs wherever possible and is probably hostile to this Buck Rogers talk. Remember around this time, there were grumblings out of the Truman Administration about why do we need the Marine Corps anyway.

I think the Navy brass finds a way to keep the research going, particularly considering the need to keep the Navy relevant. The Army Air Corps at this point is selling the A-bomb carrying bomber as the wave of the future and cheaper than all these carriers the Navy is talking about funding. In OTL, there was a very nasty political/congressional fight over the issue culminating the ‘revolt of the admirals’, that’s what it was called believe it or not. The Truman administration wound up siding with the Air Corps and the Navy found itself constantly on the backfoot.

In this TL, the rocket/satellite program is something the Navy can use to stay relevant, so the funding continues by nook and cranny. Even if the funding is completely shutdown the idea and some infrastructure is in place and someone else can pick up the slack. Someone like Howard Hughes or someone in the corporate world who can see the future benefits of the project.

Also, research into the Atlas rocket program started in 1946 OTL. It was canceled and restarted several times and not really taken that seriously until Sputnik. In this TL, the research program continues without interruption.

So, we’re in the mid to late 1940s and the program is surviving. We’re about ten years ahead of OTL. I suspect they would be able to pull off a Sputnik like launch sometime around 1947 or so, the world is stunned as a satellite orbits the planet beeping radio signals back from space.

Remember in OTL, the US Military managed to get a V2 to the edge of the atmosphere at the end of 1946 to take the first pictures of the earth from Space. Based on that, I think it is reasonable to get a satellite into orbit in the mid to late 1940s.

So, we have a functioning space program in the late 1940s working towards a series of satellites into orbit to help the Navy communicate. At this point, even the Truman administration would acknowledge there may be something to this.

At this point, Robert Heinlein and his friends make a return appearance to the stage, this time as writers. With more public awareness of the Space Program, they are more in demand in the entertainment field. They can talk/write up the benefits of going into space. Public sentiment starts to grow in favor of the space program, the peaceful space program, as this isn’t being presented as dropping bombs on people, helping people talk to other people on the opposite side of the world. Rockets for Peace.

Of course, the military is fully aware of the military applications and the intelligence services are latching on to the concept of spy satellites.

The boulders are rolling towards an active space program.

Also, other countries take notice. The Russians will follow the path they did in OTL and start an active rocket program. How much they can accelerate is in an unknown to me, I suspect that Stalin would not take kindly to falling behind the Americans, but don’t know how much he would want to divert from the A-bomb program.

At this time France had a small rocket program. I could see the French wanting to push it forward as push they’re still a great power. Several other countries may look at putting resources into a rocketry program.

Heinlein and his friends start talking up the next step, a man in space. The Space Craze hits mainstream culture earlier and has had an impact.

At the same time, Project Mordoc comes to the forefront in Great Britain. Shortly after the end of World War Two, the British Aeronautical Society advanced a proposal to put a man into space using captured V2 technology. NASA experts who examined the proposal years later said that they were ten years ahead of everyone else and if it had been implemented that there would have been Manned space suborbital and orbital missions around the early 1950s. The reason it didn’t happen was decisions by the Labour government lead by Clement Atlee in the United Kingdom. They decided to allocate resources into Atomic and more conventional aeronautical research. The United Kingdom was close to, if not broke by this time. The Atlee Government was expanding the Welfare state dramatically and was wanted what little resources they had to go to that.

Here we have an example of the practical applications of rocketry and the Atlee government may look at the proposal differently. If not, the Americans are more likely to be thinking along the same lines. Either way, resources would have been allocated earlier to manned space research than in OTL.

I’m not saying that the Mordoc project will be the one implemented, just that the logical progression after the satellite in orbit will be towards manned space flight. The American public will be looking at space at a much earlier point in history than OTL.

I’m not sure if it will still be a Navy project at this time, the newly formed Air Force will no doubt be very jealous of anything it seems as encroaching on its territory. Space, just beyond the sky, would be seen as theirs. Depending on how the various political/bureaucratic infighting takes place, we could wind up with a new agency to oversee manned spaceflight. Whatever the early progenitor of NASA was, could be put in charge of putting a man into space.

They will be in the late 1940s and early 1950s as this project starts up. The Americans are leading with the Soviet Union trailing behind and looking to jump ahead of the West. At the same time, there may be some other smaller programs, the British and the like.

The Americans aren’t in much of a race as they beat the Russians into space. There is some fear of them, but not the same level as OTL. The Russians will gain on the Americans, particularly if the Americans are complacent.

I would say the Russians are probably a couple of year behind the Americans and manage to put a satellite orbit in late 49. This will be right about the time they detonate their A-bomb, which could have been spotted by an early version of a US spy satellite. The Korean War breaks out and the McCarthy craze sweeps America. The Americans get serious about maintaining their lead in space, particularly as the American public realizes that missiles could be sent towards them.

So, we’re in the early 1950s and the Space race is really on.

I’m not sure who puts a man into space first. It would be much earlier than OTL clearly. Lets say it’s done about 1953 or so.

 

[Craig]

I suspect they would be able to pull off a Sputnik like launch sometime around 1947 or so, the world is stunned as a satellite orbits the planet beeping radio signals back from space.

Small quibble. I suspect that first satellite launch vehicle would be more like the smaller, multi-stage rockets used by Explorer 1 than the modified R-7 rocket used for Sputnik.

 

[Arkenfolm]

Another thought--Theoretically, an underground nuclear bomb could launch a satellite into space. During one underground nuclear test in the mid-50s, calculations prove that a steel manhole cover would have been launched into orbit had it not been vaporised. So maybe have an early nuclear test be underground (for secrecy, for safety, who knows) and have it launch some similar object sky high and someone puts two and two together and realises they've made the world's most powerful gun and the Jules Verne-style cannon is actually feasible. Problem at that point is making a satellite that can survive the launch since that's an insane amount of G-forces to survive. This sort of "hole in the ground" launch system is fairly limited too in terms of what you can launch, since for a bigger satellite and probably manned spaceflight you'll need the famous Project Orion nuclear pulse engine (i.e. shooting atomic bombs out the back of the ship and letting them slam into a pusher plate).

So this possibly means the first satellite before 1950 and perhaps also means the Orion drive is seen as a perfectly reasonable way to launch something into space. Maybe with knock-on effects like Project PACER is seen as a reasonable way to generate energy and other "peaceful nuclear explosions" programs. Downside is the environmental/anti-nuclear movement would come down hard on spaceflight meaning things might not be much ahead of OTL, but if the nuclear lobby/space lobby is strong enough and there's a strong belief that space activities can save the natural environment from hydro dams or mining and make green energy both cheap and environmental (for when global warming becomes a concern) then it might be mitigated.

Alternatively, you might have the nuclear launches go away entirely in favor of something like Gerald Bull's Project Babylon space gun. A gun that size (Bull's gun had a 1 meter bore) could launch small, sturdy satellites and fulfill at least some of the demand for space satellites. That could get military funding too if theoretically one could alter the gun's trajectory and let it point directly at [insert Soviet/Chinese city] and drop some nuclear artillery shells--the shells are cheaper than a missile and with some artillery tractors or a train it could be moved about and thus potentially difficult to eliminate in a nuclear war. I'm not sure how early you could have space gun technology and the capability to launch any sort of satellite which could survive the gun being fired, but it's obviously a very old and popular idea thanks to Jules Verne.

 

[NHBL]

There is quite a bit of winking and nodding going on in "Reach for the Skies" over the Navy's place in running Skywatch. Yeah, sure, it's all about developing spacecraft technologies (and the applicability of said technologies to torpedoes and submarines is purely coincidental). Big rockets are still a ways off, but the bazooka...

It's not so much winking and nodding--though there IS some of that--as that the demands of the two environments are extremely similar in many ways. If the navy expends skywatch funding for something unrelated, like guns, three will be hell to pay--but dual use, like gyro guidance, life support, computing machines, are legitimately useful for both.

Alternatively, you might have the nuclear launches go away entirely in favor of something like Gerald Bull's Project Babylon space gun. A gun that size (Bull's gun had a 1 meter bore) could launch small, sturdy satellites and fulfill at least some of the demand for space satellites. That could get military funding too if theoretically one could alter the gun's trajectory and let it point directly at [insert Soviet/Chinese city] and drop some nuclear artillery shells--the shells are cheaper than a missile and with some artillery tractors or a train it could be moved about and thus potentially difficult to eliminate in a nuclear war. I'm not sure how early you could have space gun technology and the capability to launch any sort of satellite which could survive the gun being fired, but it's obviously a very old and popular idea thanks to Jules Verne.

Making the gun mobile will NOT be easy!

 

[Arkenfolm]

Making the gun mobile will NOT be easy!

The Schwerer Gustav, largest artillery by bore, was carried by trains. And of course the Space Shuttle was carried by the crawler-transporter. So it seems possible to engineer a vehicle that can launch a giant nuclear shell from the United States to Moscow, Vladivostok, Pyongyang, or some Chinese coastal city and in the time it takes for the shell to fall and a second strike to be launched, move far enough away, or alternatively if the enemy launched a first strike, could move far enough away to launch its own shells. I think a rail-based space gun would be interesting, especially if it didn't require a broad-gauge track. The locomotive would be valuable for hauling heavy cargoes (like that giant iron ore train that operates in the Mauritanian desert).

Or we could imagine the "mobile" part gets cancelled and what's left is just the space gun, maybe somewhere on the West Coast or in Maine (or if Canada permits it, Newfoundland--Gerald Bull was a Canadian after all!). Sucks if you have to live near it, but it could still insert satellites into polar orbits and if big enough, counteract a high latitude like Maine or the PNW or Alaska. And in a nuclear war, it could be a priority target and spare the single-use missile silos (which have longer range anyway).