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Nazi “Sun Gun” references

 AARRRGH, blather, Crazy, history, Hmm..., Meh., Patreon, projects, spacecraft, ಠ_ಠ  5 Responses »
Mar 202017
 

One of the oldest and most tiresome of the “Nazi Wunderwaffen” myths is that of the “Sun Gun.” The idea is that the Nazis were found to have been working on the design of an orbital mirror, miles in diameter, that would have reflected sunlight to the surface of Earth in such a way to cause enemy cities to burst into flames. This idea first hit the US press quite soon after the defeat of Nazi Germany, and *before* the nuking of Japan. Several articles appeared in the New York Times on the topic beginning in late June, 1945, and the idea reached its peak with an illustrated article in Life Magazine in July, 1945.

The “Sun Gun” was claimed to be a circular mirror one mile in diameter, orbiting at 5,100 miles. The mirror, it was claimed, would be made from large cubical and pressure-tight blocks, providing *vast* internal volume for the crew and their crop of oxygen-producing pumpkins.

Small problem: it’s BS.

Now, there *were* ideas for vast orbital mirrors. Hermann Oberth had proposed such a thing as far back as the 1920’s, so an orbital mirror was not unknown as a concept in wartime Germany. And in reading the lean details in the articles, it’s clear that what is described is the Oberth mirror as described after a round of “telephone.” The basic idea is Oberths, and Oberth even gets a shout-out in the articles, but Oberths ideas got mutated and bent out of recognition. Not leastways because an orbital mirror a mile in diameter 5,100 miles overhead *cannot* set a city, or even a dry piece of of tissue paper on fire. The basic physics of optics prohibits that. Thought experiment: take a mirror one inch in diameter. Can you use it to start a fire? If it’s precise enough and close enough to the target… sure. Now, move that one-inch mirror 5,100 inches from the target. Gonna set anything on fire *now?*

I suspect what happened is that the the US Army officers who reported on the “sun gun” were simply told about the Oberth mirror – which, by the way, was a far less insane idea than the “sun gun” in that it was essentially foil rather than a large solid structure – by Germans who either wanted to screw with them or, like von Braun, wanted to pump up their apparent usefulness to the US military in the hopes of getting transferred to the US. Given the conditions in post-war Germany and the risks of getting sucked into the black hole of the Soviet Union, it would make sense for *anyone* to try to wrangle a ride to the US for an actual job.

I have gathered together scans of newspaper and magazine articles on the subject and mashed ’em into a PDF file which I have uploaded to the 2017-03 APR Extras Dropbox folder. This is available to all APR Patreon Patrons at the $4 level and above. If interested, check out the APR Patreon.

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 Posted by at 10:32 am

Trumps Proposed NASA Budget

 Hmm..., news, science, spacecraft  9 Responses »
Mar 192017
 

Trump’s budget would cut NASA asteroid mission, earth science

On the plus side: “Earth science” is being cut. Now, I’m not opposed to “Earth science,” it’s simply not NASA’s gig. The NOAA would seem to be the proper place for that, just like funding for ISS should come not from the NASA budget but from the State Department. On the downside, the asteroid capture mission seemed to me like one of the few useful missions for Orion/SLS.

A more involved discussion of what’s cut is HERE. Also cut is the Europa lander and NASA’s education program.

NASA’s overall budget is proposed to be cut 0.8% over the previous years. This is small compared to other proposed budget cuts across the federal budget… but it’s *YUUUGE* compared to the cuts that are happening in the entitlement programs. And that’s sad, given that entitlements are the areas that are sucking up the biggest chunk of the government and only getting bigger.

Here’s a thought: for a ten-year period, let’s flip the Medicare and NASA budgets, and then see how things stand.

 Posted by at 11:48 am

A modicum of fear-mongering to brighten your weekend

 awesomeness, blather, Hmm..., news, Nuclear Pulse Propulsion, nukes, projects, science, science fiction, spacecraft, weapons  2 Responses »
Mar 192017
 

Mini-nukes and mosquito-like robot weapons being primed for future warfare

Most of the article deal with the threat of nanotechnological weapons. I’m personally not terribly concerned about them… in theory they’re nightmares, but in practicality the chances of a mechanism the size of  a bacteria functioning for very long in the wild is low. “Nano-scale” metal is extremely fine dust… dust that will oxidize almost instantly in an oxygen environment. Dust that has such a vast surface area to volume ratio that thermal control would be virtually impossible.

I suspect it’d be possible to design nanites that will function in  specific environments. But The “gray goo” threat seems to me unlikely.

The headline contains a reference to something else that interests me more than nanites: “mini nukes.” But here again, the description seems more sci-fi than practical:

Nanotechnology opens up the possibility to manufacture mini-nuke components so small that they are difficult to screen and detect. Furthermore, the weapon (capable of an explosion equivalent to about 100 tons of TNT) could be compact enough to fit into a pocket or purse and weigh about 5 pounds and destroy large buildings or be combined to do greater damage to an area.

“When we talk about making conventional nuclear weapons, they are difficult to make,” he said. “Making a mini-nuke would be difficult but in some respects not as difficult as a full-blown nuclear weapon.”

Del Monte explained that the mini-nuke weapon is activated when the nanoscale laser triggers a small thermonuclear fusion bomb using a tritium-deuterium fuel. Their size makes them difficult to screen, detect and also there’s “essentially no fallout” associated with them.

The description seems to be a miniaturized version of an inertial confinement fusion system… lasers causing a pellet of fusion fuel to implode. So far in order to get a pellet the size of a grain of sand to fuse has required a laser system the size of a  warehouse; compressing all that down to the size of a briefcase seems… optimistic.

Still, *IF* that compression becomes possible, then these mini-nukes need to be put into production *now.* Not just for the military potential… but more importantly because they would finally make Orion propulsion clean and reasonably cheap.

What causes fear among the author and subjects of this article would cause great joy among people able to envision a wider view.

 Posted by at 3:10 am

Zero-G film making

 aircraft, art, awesomeness, youtube  1 Response »
Mar 192017
 

The forthcoming Tom Cruise movie “The Mummy” features a scene where a C-130 flies into a  flock of brdis and plummets from the sky. The characters sitting in the cargo hold are then tossed hither and yon. Normally in a big budget flick this would probably be done with CGI. Maybe some wire work. But this time they went the “Apollo 13” route and actually built a set inside a modified jetliner, and shot scenes while the jetliner performed parabolic “zero g” maneuvers.

 Posted by at 2:26 am

Bread and circuses… just no bread.

 AARRRGH, Crazy, dumbassery, Forward!, Hmm..., news, politics, ಠ_ಠ  1 Response »
Mar 192017
 

How hard is it to make bread? Well… if you have adopted socialist policies, I guess it can be real hard.

Venezuela has a bread shortage. The government has decided bakers are the problem.

Due to the sort of brilliant economics we could expect from a President Sanders or Warren, Venezuela doesn’t have enough wheat to make the flour needed for a sufficient supply of bread. Consequently, bakeries that are selling their very limited supply of product at elevated prices – you know, basic supply and demand – are getting into legal trouble with what passes for the government.

 Posted by at 1:53 am

Hydrofoils

 awesomeness, history, ships  9 Responses »
Mar 172017
 

Here’s a PR film from the US Navy, circa late 1960’s, extolling the virtues of their hydrofoil vessels. Hydrofoils, like jetpacks and flying cars, are old technologies that always seem to scream “future;” but unlike jetpacks an flying cars, hydrofoils have actually entered service. Just never with the US military, with the exception of a handful of the Pegasus class patrol bats (in service from ’77 to ’93). Cool as they were, they just never seemed to quite catch on… they made for some very fast ships, but at considerable expense, and a whole lot of maintenance. And I suspect there was always some paranoia about just what would happen if a hydrofoil ran into a log or a boat or a whale while at top speed.

The film includes some spectacular footage, and some just awful background music.

While hydrofoils had their day fifty years ago, the somewhat similar SWATH (small waterplane-area twin-hull ) concept has popped up much more recently. Witness the “Ghost” from 2014:

 

 

 Posted by at 2:06 am

Boeing C-5 Proposal display model

 aircraft, history, models, projects  2 Responses »
Mar 172017
 

Recently sold on eBay (for $500) was a display model of the Boeing proposal for the C-5 program, which of course lost out to Lockheed. The Boeing design (circa 1965) was vaguely like a Lockheed C-5 merged with a Boeing 747… roughly the configuration and fuselage size of the C-5, but with the raised upper deck and the standard “jetliner” lower tail surface of the 747. I have surprisingly little on the Boeing C-5, but I do have some fairly detailed diagrams of a civilian passenger version, and a few derivatives. Interestingly, while this was clearly part of the genesis of the 747 – which by every metric was a far greater success for Boeing than the C-5 was for Lockheed – it was actually a model 757. As the design effort continued the 747 designation would become the jumbo jet, while the 757 designation would be applied to a much smaller jet.

 Posted by at 1:47 am

That Was Odd: Christmas in March

 blather, Crazy, That Was Odd  18 Responses »
Mar 162017
 

This one is a tad odder than the reappearing star. At one AM on March 1st (I can narrow this one down because I sent a text to a friend) a series of nuisances reached a pinnacle.

Throughout the night there had been a number of odd noises, like *things* bumping up against the side of the house. Some years ago a horse wandered into the corner of the house; this sounded like a smaller version of that, so I assumed that it was something like a deer. In addition to the *thumps* there was some “clacking” sounds associated with the bumps, so I assumed that it was deer antlers bonking against the side of the house.

This occurred several times over a span of three or four hours. Several times I looked outside, but didn’t spot any deer. Shrug.

Then at about 1 AM anomalous noises moved from the side of the house. I’m sitting there doing some CAD drafting, the TV on making some background noise. Even the cats were bored out of their minds; the joy of running around like idjits had burned itself out and they were reduced to a vegetative state. So I hear this noise overhead. I was unsure if it was a noise out in the world or it it was on the TV, so I put it on mute, and the noise occurred again.

What it sounded like was a smallish hoofed animal stomping around on my roof.  My house does not have an attic, so sounds on the roof come through pretty clearly. But a roof is not a naturally tenable place for a hoofed animal to get to in the first place, so my first thought was that I was just hearing things. But then I noticed that both Raedthinn and Buttons were staring intently at the same spot in the ceiling. Whatever I heard, the cats heard too. Then it stomped around a bit more.

Curiosity won out over inertia, but caution was also called for. Coyotes and semi-wild dogs are reasonably common out here; armies of raccoons are not unknown, and there have been reports of mountain lions and even *humans,* if you can believe it. So, I grabbed a coat, shoes, 2,000 lumen flashlight and a 12 gauge and stepped out to see what was on my roof.

Turns out… nothing. Not a damn thing. Except for a light coast of snow, maybe a quarter inch deep, sufficient to show footprints, of which there were none. None on the roof, none around the house. I walked all the way around the house and checked out the whole roof; nothing disturbed the snow except my own footprints. The snow was there from earlier in the day, so any deer bumping into the house should have left tracks.

Since there were other witnesses in the form of at least two cats, I know that the sounds were real. Under other circumstances I’d suggest that the sounds were the result of the house settling or otherwise flexing due to temperature or even geological effects (we get the occasionally just-barely-detectable earthquake). But I’ve lived here since 2004, and while I’ve heard this house make a bunch of noises, I’ve never heard anything resembling “hooves on the roof.”

Speculating further from “settling,” the only thing that kinda seems halfway practical is that a very large raptor or eagle landed on the roof, just on the tips of it’s claws. I suppose if that were to happen, it might not leave visible marks in shallow snow. But a tiptoeing, stomping giant bird of prey doesn’t seem entirely likely either.

So this one falls into not only the “that’s odd” category but also the “the universe is screwing with me” category.

 Posted by at 8:39 pm
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