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Based on the description, it almost sounds like someone scammed them into spending (presumably) a lot of money on something pretty useless.
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Why do you think launching objects into space via kinetic energy is useless? It's actually quite brilliant and similar systems are now in use today[1].

1. https://www.thedrive.com/the-war-zone/43079/space-launch-sta...

"In use" is quite a stretch for Spin Launch; to my knowledge they've only launched the one test. Also a centrifuge is not really similar to a gun.
One major issue is that you need a considerable acceleration to achieve a velocity sufficient for orbit - and unlike a rocket, a space gun would need to achieve that on the ground.

It would also need to achieve a very high speed for the object at almost ground level, in a dense atmosphere with high friction.

Both would require a fairly sturdy payload, but you want space payloads to be comparatively delicate so you need to put less mass into orbit.

A centrifuge at least deals with the first issue since the required acceleration is independent from the centrifuges size, you just make more rounds. Still need to deal with the centrifugal force, though.

> Both would require a fairly sturdy payload, but you want space payloads to be comparatively delicate so you need to put less mass into orbit.

Wouldn’t you get a big reduction in mass from not needing to bring enough fuel to get up there?

You could put the space gun at high altitude to start with to reduce the air resistance.

With regards to being delicate, we already have rocket assisted guided artillery shells. These require complex electronic and can survive the high acceleration.

>space gun at high altitude

Also called first stage of rockets ;)

>we already have rocket assisted guided artillery shells.

They don't have cooling/heating-systems, solar-panels no special instruments or optics no isolation AND they don't have to be lightweight, if you combine all that together, it gets so expensive creating such a satellite (and that every single time because of customization) it's probably cheaper just to buy/rent a rocket where you can (maybe) share the payload. I mean, even the vibration of a rocket can severely damage a satellite.

The point of having the first stage fuel on the ground is you don't have to carry it up there. If you can design something to withstand the shock then it is worth doing. Unlikely to be suitable for all applications but there are likely some which fit.
>Unlikely to be suitable for all applications but there are likely some which fit.

Yes artillery shells, that's what "Project Babylon" is about ;)

Project harp worked. This gun was made by the same person, Gerald Bull. It was obviously enough of a threat to get him assassinated.
It worked for launching things into space. It did not work as a weapon for the various reasons the wikipedia article points out.

What got him assassinated is more likely his other work referenced on his Wikipedia page:

>The Iraqis then told Bull they would go ahead with the project only if he would also help with development of their longer-range Scud-based missile project.

>Watching development of the gun, Israel feared it could be used to launch nuclear weapons, but the re-designed Scud missiles were of greater concern at that moment.

Any clues about who murdered him? Is the case still open?
The requirement that payloads must be able to survive such brutal acceleration does initially appear to be a limiting factor for this kind of technology, but it does have compelling advantages too.

First, there's the brutal tyranny of the rocket equation[1]. Not only must a rocket burn fuel to lift it's payload into orbit, it must also burn fuel to lift all the fuel it will burn on the way plus the rocket parts to contain that fuel and the engines to burn it. With a gun, you only have to put in enough energy to accelerate the payload and capsule to escape velocity. This is far, far more energy efficient! Also, many alternative energy forms are possible to use in such a gun, including electricity.

So what? What about that brutal acceleration problem? Although complex electronics, etc. can be built to survive such stresses, it's a huge design requirement for payloads that might never face such forces again once in orbit or beyond. However, this method of launch is ideal for getting raw materials into space for use in orbital fabrication. Getting big things into space is massively expensive because rockets are so horribly inefficient. If we fire the raw materials up via space-gun and then use them to fabricate things in space, those things could become orders of magnitude cheaper. Mining materials in space is obviously the way we eventually want to go, but that's going to take a while. Space-guns could be a crucial stepping stone.

The Babylon project, had it worked, might not have been terribly useful for Iraq in the 1980's. However, if space fabrication takes off before space elevators are a thing, kinetic launchers will likely have their day.

[1]https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation

What if, instead of a gun which imparts massive accelerations on the payload, we instead use something with lesser acceleration. I’m thinking of a hybrid between an elevator, a slingshot, and a railgun. The point here is to get to escape velocity without a huge acceleration. The payload would sit on a platform lowered deep into a vertical shaft, counterbalanced by a relatively heavy mass suspended from the other side of a pulley. The start of the launch would involve dropping the mass and after hitting terminal velocity of the payload/mass system, the railgun-like magnetic acceleration would start. At the end, just the launch vehicle would come flying out of the hole and into space.

Have I run any numbers? No. But I’m going to!

Would love to see the numbers on this!
FYI, in case you're unfamiliar with Meopotamian geography and history: the Babylonian Empire and modern-day Iraq overlapped by a lot, and there are plenty of artifacts and ruins to be seen around there, at least those that haven't been pulverized and vaporized by millennia of instability and warfare.

When Jonah's sent to the city of Nineveh on a mission to urge them to repentance for their sinful ways, that's pretty much Iraq too.

So an absurd space gun called Babylon fits right in with the narrative in those parts.

Also a classic nationalist move to play up the connection to past greatness, positioning themselves as the natural inheritors of such.
The lead engineer, Gerald Bull, sounds like a real piece of work. He just really really wanted to make big guns!
And for that he paid with his life. It's believed he was killed by the Israelis.
Unsurprisingly, that seems extremely murky to me. If the Israelis had a problem with Bull, why didn't they take it up with Canada or even the US, who would have given them a friendly hearing and been able to find ways to stop Bull without assassination? I mean, a few mill in the bank and a cushy ballistics research job at Lockheed would seem to be reasonable. What am I missing?
Their extrajudicial killings are about sending a message, not stopping one particular person. This is a half century old policy at this point.
Im not stating any pro or anti statement on Israeli policy here, but if your policy is to send a message by assassination and you spend half a century doing it, perhaps the message is not getting through.
Knowing that we have to create a Babylon project after the Earth-Minbari war anyway, Irak took a lead and decided to use the Babylon name so that nobody would dare to attack us in the first place.
"Project Babylon" is the name I use whenever I start a project that is too ambitious and I expect it to collapse before I succeed in challenging the heavens, leaving being a rubble of technical debt that inhibits future progress.
how do you deal with the multiplicity in your graveyard. do you number them ? Babylon-1. Babylon-2. etc ..
Having one boondoggle is going at a time is enough for me.

Once the old rubble has finally been cleared away and memory of the failure has started to fade, that's when I start on a new one, and since the old one never went anywhere there's no harm reusing the name, right?

Interesting story, especially the part where the Canadian scientist got assassinated by (probably) Israel.