Space Gun Built

Let's suppose that the initial events of Verne's A Voyage From the Earth to the Moon took place: A great space cannon is built in Florida. It's an immense project, of course, but it wasn't entirely beyond the technology of the time. When the time comes, the capsule doesn't contain people (for obvious reasons), but the sturdiest cameras available, with clockwork mechanisms to take pictures automatically. Pictures of the Earth, pictures of the Moon. The capsule lands by a parachute mechanism, all fully automated by necessity. What would be the impact on the public consciousness? Or are the technical challenges and difficulties such that in the late 1860s and early 1870s, this is ASB material?
 
Definitely ASB.

Space guns are not really possible on a planet with a thick atmosphere (like Earth). A projectile launched from the surface of the Earth would need to be travelleing at about 10km/s to have enough momentum to reach the moon - if the Earth had no atmosphere. The thick lower atmosphere of the Earth would mean that that 10km/s would become 5km/s very quickly due to air resistance. To overcome this air resistance the launch velocity would have to be even higher - say 20km/s. But then this higher launch velocity leads to even more air resistance requiring an even higher velocity to overcome.

Not only would a space gun waste a whole lot of energy overcoming low-atmosphere air resistance, but this energy would all eventually turn into heat, turning the capsule into molten goo very quickly. You know how spacecraft coming back to Earth heat up on reentry? Well, that heat is just barely bearable largely because returning spacecraft are able to slow down a lot in the upper atmosphere so that they are moving quite slowly (less than 1km/s) by the time they reach the lower atmosphere. Your space gun projectile would be doing the opposite- travellinf fastest in the lower atmosphere and skowing down as it got higher. High speed in the thick low atmosphere would create much more of a heat problem.

Rockets are incredibly inefficient because they not only have to lift a space capsule but also habe to lift all of their own fuel. However, rockets are the only space lainch method used in OTL? Why is this? Simply because a rocket is the only way we know to save most of the acceleration for the thin upper atmosphere. Rockets can go slowly at first until they're out of the lower atmosphere and then can accelerate. A space gun peojecticle can't do this.

There are lots of OTL proposals for space-gun-like future launch systems (but using a mglev track rather than gunpowder), becauee they would save a ton of energy compared to rockets. However, they all require some sort of way to get out of the lower atmisphere: a giant tower or a kilometers-long gun barrel that are beyond our current engineering capabilities, so clearly not possible in the 19th century.
 
Thank you. I wasn't too concerned about the capsule's mechanisms; it was the launch itself that I was dubious about. And rightly so.
 
Here’s the objections raised by @telynk in video form:

Basically, we do have non-rocket options like launch loops that are technically feasible with modern tech, but require massive investment in both land and money. Now, maybe, maybe we could have built one if most of the resources dedicated to rocketry went to this instead, but no earlier than the 1970s in this layman’s estimation. Certainly not the 19th century.
 
Space guns are not really possible on a planet with a thick atmosphere (like Earth). A projectile launched from the surface of the Earth would need to be travelleing at about 10km/s to have enough momentum to reach the moon - if the Earth had no atmosphere. The thick lower atmosphere of the Earth would mean that that 10km/s would become 5km/s very quickly due to air resistance. To overcome this air resistance the launch velocity would have to be even higher - say 20km/s. But then this higher launch velocity leads to even more air resistance requiring an even higher velocity to overcome.

Not only would a space gun waste a whole lot of energy overcoming low-atmosphere air resistance, but this energy would all eventually turn into heat, turning the capsule into molten goo very quickly. You know how spacecraft coming back to Earth heat up on reentry? Well, that heat is just barely bearable largely because returning spacecraft are able to slow down a lot in the upper atmosphere so that they are moving quite slowly (less than 1km/s) by the time they reach the lower atmosphere. Your space gun projectile would be doing the opposite- travellinf fastest in the lower atmosphere and skowing down as it got higher. High speed in the thick low atmosphere would create much more of a heat problem.

Aren't you mixing the acceleration of gravity (9.8m/s²) with the escape velocity from earth? I mean, in vacuum one second after the launch the object would be 10,000 meters high and the speed would decrease to 9,990 m/s, then after two seconds the object would reach 19,990 meters with speed decreasing to 9,980 m/s and so on...
 
Aren't you mixing the acceleration of gravity (9.8m/s²) with the escape velocity from earth? I mean, in vacuum one second after the launch the object would be 10,000 meters high and the speed would decrease to 9,990 m/s, then after two seconds the object would reach 19,990 meters with speed decreasing to 9,980 m/s and so on...

The value of the escape velocity I googled.

I did screw up the math somewhere else though. The force of air resistance is proportional to the speed of an object and somehow from that I assumed that the delta v (loss of speed) due to air resistance would also be proportional to speed. This would mean that if a capsule launched at 100m/s slowed to 50m/s before it left the atmosphere, a capsule launched at 10km/s would slow to 5km/s. This is very much not true because the faster capsule would spend less time in the atmosphere. So there is a speed which is fast enough for the capsule to leave the atmosphere before it slows down too much and wastes too much energy. The problem isn't actually the air resistance itself (in terms of energy lost) but the heat it produces.
 
https://en.wikipedia.org/wiki/Project_Babylon

A space gun (or at least a gun capable of firing into space) was actually under construction in Iraq until the Canadian designer was assassinated, possibly by Israel or Iran. It would also absolutely kill any occupants and would almost certainly destroy any radio equipment the 1800s could build.

If anyone is interested in learning more about Gerald Bull and the Babylon Gun, there is a very good biography of Bull’s life called Arms and the Man.
 
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