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Project A119 (wikipedia.org)
150 points by benbreen on Dec 11, 2018 | hide | past | favorite | 49 comments

Fascinating. I never knew the Mr. Show segment “Let’s Blow Up the Moon”[1] had any basis in fact.

[1] https://m.youtube.com/watch?v=GTJ3LIA5LmA

love the part where the astronaut says "I walked on the moon. Did a push up. Ate an egg on it. What else can you do with it?"

also love the fact that his voice kinda sounds like that of George HW Bush.

This era of science always fascinates me.

First landing on the moon? July 20, 1969. First satellite launch? January 31, 1958. 11 years, 5 months, and 20 days.


The clock should really start in June 1944, with the first rocket to cross the Karman Line: a V2 ballistic missile. In many ways the moon landings (and plans to nuke the moon) were the continuation of the war effort's tremendous pace of technological improvement. The early rockets were primarily designed as ICBMs with peaceful payloads as secondary adaptations.

If you look at the early space programme it can really be seen as a set of milestones directly aimed at the manned moon landing - orbital manned flight with safe landing (Mercury), two-man operation (Gemini), space suits, EVA, docking, and so on.

> The early rockets were primarily designed as ICBMs with peaceful payloads as secondary adaptations.

Von Braun was interested in astronomy and space exploration well before the war. He is quoted as saying "the rocket worked perfectly, except for landing on the wrong planet." - referring to the Sept 7 1944 launch. In essence it was a peaceful rocket turned into an ICBM and thankfully later on returned to its peaceful status.

And on a side note: imagine being Von Braun after the US handed him the keys to their state of the art space program with a cold war sized budget. Beyond a dream come true.

> Beyond a dream come true.

Luckiest man in the war. He could have been killed in any number of ways during the war, he managed to surrender to the Allies and not the Soviets, and they chose not to hold him responsible for the 12,000 slave labour deaths of the V2 programme. Not all the beneficiaries of slave labour did so well. https://en.wikipedia.org/wiki/Fritz_Sauckel

Von Braun was also the recipient of big time image rehabilitation courtesy the US, in exchange for his work after scooping them up in Operation Paperclip. Not to take anything away from his instrumental role in US rocket development, but I'd take any quotes and motivations with a grain of salt.

Along these lines, I've always been fascinated by Operation Paperclip [0], the US effort to collect Nazi scientists that including Wernher von Braun (of V2 infamy and Saturn V fame).

As Tom Lehrer sang [1], "'Once the rockets are up, who cares where they come down? That's not my department,' says Wernher von Braun."

[0]: https://en.wikipedia.org/wiki/Operation_Paperclip [1]: https://www.youtube.com/watch?v=TjDEsGZLbio

Should note that the US benefited tremendously from the emigration of thousands of highly trained scientists well before the war started due to European anti-semitism. Einstein was perhaps the most famous but there were so many more who essentially modernized the US University system, and even contributed to the War Effort (e.g. the Manhattan Project).

Interesting. I wonder if we could somehow return to that clip of progress in science and technology. If we did so, who knows where the US might have been now, in terms of science and technology?

Arguably the whole Moore's Law era proceeded at that clip, and it's given us the iPhone, GPS, various starts at ""AI"", etc.

The real problem with returning to the space race was that it was fundamentally a public sector project. People seem to forget that it was the state that put a man on the moon. In 2018 the key question for such projects would be not "how can we benefit humanity" but "who gets to keep the profit"?

Or even more fundamentally, "is there any profit for someone to keep?"

It's not like the Apollo program was the space equivalent of a state owned rail system -- capable of making money for the first private owner to take it over. It was always "in the red" if you measure such things in business terms. People twist themselves in knots trying (IMO) to assign dubious "spinoff" benefits, with dollar signs attached, to NASA work.

Give up on trying to justify all scientific research in the vocabulary of business, I say. I support public funding for space probes, astronomy, high energy physics, and all sorts of other things that expand the frontiers of human knowledge without being likely to generate new commercial products or profits.

Agreed, I was always fascinated with the early exploits, some of them captured in this Wikipedia list:


only slightly less crazy, they actually DID this:


see soviet union section for their equivalent: https://en.wikipedia.org/wiki/Peaceful_nuclear_explosion

I'm intrigued by these atomic re-landscaping proposals.

Cooler coastal air could be drawn into California's dry, hot inland valleys by blasting a number of large, artificial passes through mountain ranges up and down the state.

And atomic explosions could ameliorate intense traffic problems in Los Angeles not only by conveniently creating new passes through the Santa Monica mountains for new multilane highways between the Valley and the West Side, but also as a means of clearing gridlocked intersections.

I think for this to happen, there would need to be demonstrations of the safety aspects of using nuclear weapons.

Can you imagine trying to justify this project to the public? It would be a nightmare: "Nuclear explosions planned outside Los Angeles"... it would likely trigger a mini-freakout.

How times have changed since people would drive to Las Vegas and party next to a nuclear test...


Clearly not worth the trade-offs in hindsight but how can you fault them for wanting to find constructive used for the technology?

Almost like a late 70s tv show https://www.youtube.com/watch?v=kpjFU_kBaBE

Wow, it's as if it was taken from a Fallout game

Soviet Union did actually show their nuclear power 3 years after by exploding Tsar Bomba

Which was an utterly impractical weapon that had no use other than geopolitical chest-beating.

The same is true for every nuclear weapon.

Not really. Smaller ones are quite good for destroying a lot of stuff or killing a lot of people, which can be really useful in war. Their presence can also be good for preventing the other side from deciding it would be nice to destroy a lot of your stuff or killing a lot of your people with their own weapons. The problem with the Tsar Bomba is that it was so large it couldn't be delivered to any real target. The test required a specially-modified bomber that wouldn't have been able to make a strike in a real war.

Agreed. How many nuclear armed countries have been invaded?

The UK and India, at least.

Children, remain calm. The Falkland islands have just been invaded.

> A young Carl Sagan was part of the team responsible for predicting the effects of a nuclear explosion in vacuum and low gravity and in evaluating the scientific value of the project.

I would be interested in their research on this, from a purely curious standpoint.

Thinking about this, the interesting part is what happens when there is no air to heat and expand? From my understanding, in a chemical explosion the explosive itself releases a pressure wave of gas from the burning of the explosive. The air surrounding a chemical explosion helps carry the pressure wave further out.

But what physical material is ejected from a nuclear explosion and can it create a pressure wave? I was under the impression that the main component of a nuclear explosion is heat. Lots and lots of heat in the form of photon energy in a rainbow of EM spectrum. The destructive pressure wave is a result of the air/material around the detonation being violently heated to millions of degrees in mere microseconds.

Of course even in the vacuum of space anything within "ground zero" (can you say that in space?) of a nuclear explosion will still vaporize, producing expanding gases which can create a pressure wave. This is how I imagine a nuclear "asteroid buster" would have to work. The bomb would have to be on the surface or damn close to vaporize material from the object to influence its trajectory.

I had to double-check with the Atomic Rocketship website. You are correct in that the energy released by a normal nuclear detonation in a vacuum would follow the inverter square law, and would not transfer force as effectively over distance as it would in a fluid medium.

Note that I said "normal" nuclear weapon. ;-) The Atomic Rocketship page describes something called a Casaba Howitzer. This is basically a shaped charge version of a nuke, that discharges its energy in a beam or cone shape. Details beyond that are still classified.

Anyway, there's more than you ever wanted to know here:


Search within that page for "nuclear" or "Casaba" and have fun.

The more I read about him, the more Sagan becomes my hero. What a legend.


What a crazy time when the first thing people wanted to do when they reached the moon was blow it up. I wonder, with the mass of the moon being so much less than Earth's, would the explosion have altered it's orbit?

Nope! Wolfram Alpha puts the orbital kinetic energy of the Moon at 3.425e28 joules, or 8.186e18 tons of TNT [1]. The Tsar Bomba, the biggest nuclear weapon ever detonated, had the energy equivalent of 50 megatons of TNT (5e7 tons), which is 100 billion times smaller than the Moon's kinetic energy. The Moon is just really heavy - it's unlikely we could ever do much to change it's orbit (with current technology at least!).

[1] - https://www.wolframalpha.com/input/?i=kinetic+energy+of+the+...

What if we build a gigaton-range warhead (which modern rockets could easily lob[1]) and watch for an opportunity to deflect a comet or large asteroid? The parts I have no idea about are: how often suitable projectiles come close enough to the Moon's path that a Gt nudge would do the deed; and whether we could predict the effects of a huge nuke well enough to steer the object with the requisite precision--but it seems to me interfering with the Moon is only a bit more difficult than defending against a doomsday impact on Earth, so I hope it would be possible.

1: https://en.wikipedia.org/wiki/Asteroid_impact_avoidance#Come...

I can't currently find a link, but I've seen speculation that nuclear explosions on the moon could serve to eject some of the moon's mass. Even a small change would necessarily change the moon's orbit very slightly – and over enough time, the position of Earth-moon system would be quite different from what it would have otherwise been.

(This was proposed as a way to move the Earth out of the path of an approaching body, given enough warning, without actually having to reach the much-further-away approaching body, and alter its path.)

I don't mean to be insulting, but your question is a pretty good example of the human mind's difficulties in comprehending scale.

Yeah, and its not limited to science. When applied to e.g. economics, that is when people reach utterly wrong conclusions when evaluating different proposals.

Fascinating. Kind of sad that this was ever _considered_.

Why? Of all the places to detonate a nuclear bomb in the name of science, the moon seems a pretty safe one with little consequence to any living thing.

I don't really see it as all that different than drilling for a core sample, except in scale, but that scale still doesn't affect anything, so I'm not sure it matters.

We blew up a bunch of Pacific islands and various other places with hundreds of explosions for no purpose other than to make sure we could more effectively kill people. Nuking the moon is positively benign by comparison.

It would have been scientific in name only. I don't think there is any open scientific question of any great consequence where people are saying "if we could only set off a nuke on the moon, we would know for sure."

What sets my eyes rolling is the midcentury enthusiasm for setting off nukes wherever we could possibly put them. I bet there were people thinking about nukes under the antarctic ice cap, in a volcano, a major fault, a hurricane's eye...

Another factor, cited by project leader Leonard Reiffel, was the possible implications of the nuclear fallout for future lunar research projects and colonization.

What a crazy time.

Am I the only one that expected an article about Pixar?

Thank you. I wanted to make sure I wasn't the only one.

This just boggles the mind. Soon, we'll find out that the military has had time travel technology and they've been bringing back dinosaurs to conduct research experiments to build mammoth, militarized, non-mammalian militias. Believe it.

From SG-1:

Maynard: Mr. President, I'm here to bring you up to speed on a program we've been running out of Cheyenne Mountain for the past seven years.

Hayes: I've already had my top secret briefing.

Maynard: Yes, Mr. President. But not this. Mr. President, for the past seven years the United States Air Force has been sending teams to other planets by means of an alien device known as a "star gate".

Hayes: That's funny. That's very funny. My first day. This is a joke, right? I have a great sense of humor—I didn't know that you had one—but this is good because we're finding out about each other. Now I have to call the ex-President of Togo, and when I'm done, apparently, the rest of the world is coming to an end.

Maynard: The ex-President of Togo will have to wait, sir. This is not a joke.

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