Simulating Jules Verne Earth to the Moon trip?

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Discussion Overview

The discussion revolves around simulating the trip to the moon as described in Jules Verne's novel, focusing on the calculations and factors involved in such a hypothetical scenario. Participants explore the implications of acceleration, gravity, and other forces on the projectile's journey, while also considering the historical context of Verne's work.

Discussion Character

  • Exploratory
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • Some participants inquire about the specifics of simulating the trip, with a focus on calculating time, deceleration, and proximity to the moon.
  • There is a distinction made between "simulating" and "calculating," with some suggesting that the task is more about calculations than actual simulation.
  • One participant mentions the historical accuracy of Verne's work, noting that he had a relative who was a mathematics professor and that some scientific elements in the book were based on calculations.
  • Another participant highlights the need to consider drag force, which depends on the projectile's shape, cross-sectional area, air density, and velocity, complicating the calculations.
  • Specific values from the book are discussed, including the weight of the projectile, its diameter, and the initial velocity, with calculations indicating that without atmospheric drag, the projectile would only reach about 46% of the way to the moon.
  • Participants also mention the effect of Earth's rotation on the projectile's initial velocity, noting that it provides a small additional boost.

Areas of Agreement / Disagreement

Participants generally agree on the need for calculations rather than simulations, but there is no consensus on the exact methods or formulas to use, and the discussion remains unresolved regarding the best approach to take.

Contextual Notes

Limitations include the complexity of accurately modeling drag forces and the assumptions regarding the projectile's resistance to acceleration. The discussion also reflects varying levels of familiarity with aerospace and ballistics among participants.

riveay
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Has anybody attempted simulating the trip to the moon described by Jules Verne?

I've done a bit of research and found this two posts:

https://www.physicsforums.com/threads/showing-deadly-acceleration.909104/#post-5726115

https://www.physicsforums.com/threa...ship-fired-from-a-cannon.793891/#post-4985868

The first one says that it is impossible for the human body to withstand the acceleration and the second one a quick calculation of the acceleration within the cannon.

Now, has anybody attempted to simulate this considering the gravity gradient and the orbits? I know that Jules Verne made some mistakes due the knowledge current at the time he wrote the book, but still, I find it insteresting to try it out.

The factors I know are required for the simulation are:
  • Distance to the moon
  • Muzzle velocity
  • Gravity as a function of time
  • Air drag (maybe neglect it for simplicity's sake?)
Please, do let me know if I'm missing something.

Thank you very much to all! :)
 
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Can you explain what you mean by simulating?
 
Vanadium 50 said:
Can you explain what you mean by simulating?
Using the values from the book in a programme and calculating the time, deceleration and how close to the moon it would get.
 
Ah. This is more "calculating" than "simulating".
 
Vanadium 50 said:
Ah. This is more "calculating" than "simulating".
I used the wrong word there. I apologise.

So, I would really like to know how to calculate how close a project like that would be from the moon. Assuming, of course, that the people inside the capsule would resist the acceleration. I'm quite new to aerospace and more so to ballistics. I understand that the capsule is accelerated by the gas expansion whilst it inside tha cannon, but I don't have any knowledge on which formulas to use to calculate such acceleration and then, how to calculate the change in velocity due to the gravity, drag force and whatever forces I'm missing.

Any hints?
 
I studied this a little when I was in high school, and I also read the book. Jules Verne did have an uncle who I believe was a mathematics professor, so some of his science-fiction was based on actual calculations. I believe there is one place in the book where they give the result of where the point of zero gravity occurs between the Earth and moon=I believe it is at 9/10 of the distance to the moon, because the Mass of the Earth is 81x that of the moon. Anyway, if I'm not mistaken, he got that part correct. ## \\ ## Editing: A quick google is unable to confirm the math professor uncle, but I researched this topic when I was in high school in 1973, and that was what they said, if I remember, in some kind of biographical write-up that I found.
 
Last edited:
Vanadium 50 said:
Ah. This is more "calculating" than "simulating".

Isn't it an n-body simulation (with n=3)?
 
riveay said:
I used the wrong word there. I apologise.

So, I would really like to know how to calculate how close a project like that would be from the moon. Assuming, of course, that the people inside the capsule would resist the acceleration. I'm quite new to aerospace and more so to ballistics. I understand that the capsule is accelerated by the gas expansion whilst it inside tha cannon, but I don't have any knowledge on which formulas to use to calculate such acceleration and then, how to calculate the change in velocity due to the gravity, drag force and whatever forces I'm missing.

Any hints?
The most difficult part of this would be calculating the total effect of drag. It is dependent on the shape of your projectile, its cross-section area, the density of the air, and the velocity of the projectile. Only the first two would be constant during the passage through the atmosphere.
The values I got from my copy of the book were 20,000 lbs for the weight of the projectile and a diameter of 9 feet. It was fired with a velocity of 36,000 ft per sec.
With no atmospheric drag, this velocity only get you ~ 46% of the way to the Moon. You'd need ~ 378.4 ft/sec in additional muzzle velocity to reach the Moon.
Granted, the rotation of the Earth will give the projectile a bit of an extra boost. At the latitude of the launch the tangential velocity of the Earth's surface is ~1354 ft.sec. However, this would be applied at a right angle to the cannons bore, so would only add ~25 ft/sec to the projectiles velocity.
 

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