Eunoia
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--> Most recent Blog Comments Policy Impressum Maths trivia Search this site RSS Feed Eunoia, who is a grumpy, overeducated, facetious, multilingual ex-pat Scot, blatantly opinionated, old (1944-vintage), amateur cryptologist, computer consultant, atheist, flying instructor, bulldog-lover, Beetle-driver, textbook-writer, long-distance biker, geocacher and blogger living in the foothills south of the northern German plains. Not too shy to reveal his true name or even whereabouts, he blogs his opinions, and humour and rants irregularly. Stubbornly he clings to his beliefs, e.g. that Faith does not give answers, it only prevents you doing any goddamn questioning. You are as atheist as he is. When you understand why you don't believe in all the other gods, you will know why he does not believe in yours :-) Oh, and he also has a neat English Bulldog called 'Kosmo'.
Some of my bikes
My Crypto Pages
My Maths Pages
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Thursday, August 24, 2017
3 Neat Eclipse Photos :-)Over here in Germany we didn't get to see even a partial eclipse of the sun on the 21st. So I've been scanning many US blogs to see the best eclipse photos, here are three I particularly like :-This first one overlaps seven shots of the eclipse from partial through total and back to partial again. I like the way that this overlapping assembly demonstrates that the plane of the orbit of the moon around the earth is tilted about 5° off the plane of the orbit of the earth around the sun. If it weren't, we'd get a solar eclipse every month. The tilt makes them rarer. This second photo is of totality. I've enhanced it with 3 green rings around solar protuberances which are looped back by the sun's magnetic field. In this third shot, the photographer thought through ahead of time to work out where he would have to stand - and when - to get the shot. Well, actually six shots. They show the transit of the ISS space station across the disc of the sun during a partial phase of the eclipse. The other irregular dark spots are sunspots afaik. Well thought out, whoever you are! You got a spectacular photo :-) Which do you like best?
Comments (1) Monday, August 21, 2017
The Great American DarknessToday a total solar eclipse crosses the USA, casting even less light upon the Great American Darkness. Expect chaos, not just during the eclipse :-( Comments (1) Saturday, August 19, 2017
Rare SG41 crypto-machine found!Hikers, walking through the Bavarian forests near Munich, recently found a WW2 era SG41 crypto-machine which they took to be an old typewriter and turned it over to a Munich museum. Shame! Crypto geeks like yours-truly would have paid good money for that, it's very collectable.Only 1000 were built, afaik. It was designed by the famous WW2 German cryptographer Fritz Menzer, who broke Hagelin's C36 rotor machine in 1936 and showed how to cryptanalyze their own Enigma. So the German military could have known not to use the Enigma and replaced it with something better (like the SG41), but, basically, they ignored him at the time. In 1941/42 he designed the SG41 shown above, also referred to as the Hitlermuehle (Hitler's mill), which first went into production in 1944. About 1000 were built, most were destroyed by troops who realised they were losing the war. So they are pretty rare now. It uses the basic Hagelin design but improves it by having six mutually prime pinwheels and , most importantly, variable stepping. The key-space was at least 15,000 times larger than that of the Enigma which the SG41 was intended to replace. Bletchley Park did not, afaik, break it, although it seems to me to be susceptible to hill-climbing techniques (maybe that's how the hikers found it ;-) In his various attempts to improve Enigma, which he knew to be crackable, Menzer also invented the hole-filling roller (1943) which would enable a standard Enigma to have variable stepping (but needed the users to make 2 more steps); key-device 39 (in 1939) which generated paper tapes (as the SG41 did); the key-case cipher box; the key-disc lock-washer designed for use by spies; and the key-wheel, an early stream cypher. All these were purely mechanical devices, like the M-209 the Americans used. The M-209 was a lug and pin design by Hagelin, an improved C-36, without a keyboard. Afaik, Hagelin never received royalties for it :-( Tuesday, August 15, 2017
Hollywood HumourJust passing on some Hollywood Humour recently passed to me, concerning new movies to be released soon :-An instructional documentary about premature ejaculation : Coming Soon ;-) Russel Crowe starring as a cannibal who was very happy that he ate both his wife AND his mother-in law : Glad he ate her too ;-) Vin Diesel starring as a man angry about his premature ejaculation : The fast and the furious ;-) And eternal pirate Johnny Depp, whose ship Black Pearl was sunk several times, points out to Donald Trump that the ship of state is the only one that leaks from the top ;-) Friday, August 11, 2017
EclipsesOn monday evening, we had a partial eclipse of the moon over here. Sadly the sky was overcast here, so I've had to borrow this photo from a press site. These partial lunar eclipses are fairly common, but always nice to watch.Several years ago, there was a total eclipse of the sun ( a rare event) here in Europe and so the wife and I drove the couple of hundred miles into the Elsass hills which were on the path of totality. Up on the hillside so we could watch the edge of the totality shadow come racing silently along the valley below at about Mach 3 (imagine a SR71 Blackbird at sea level). First time I've had an impression of how fast Mach 3 really is :-) Some spectators there hadn't thought the eclipse thing through however. They wore T-shirts and were surprised when it got really cold even in the penumbral shadow and after totality even started to rain (the temperature had dropped below the dew-point). Don't say I didn't warn you! Now the USA is getting a total eclipse of the sun (once a century) this month. The path of totality crosses the whole of the continental US. A hundred million people or so live within a day's drive of the path of totality, so I recommend my US readers take that drive (as we did years ago), it will be the only opportunity in your lifetimes. Some car rental companies (e.g. Hertz) have overbooked already and are cancelling reservations (is that legal?):-( Dress warmly in something waterproof. Get yourselves proper eye protection, enough for everybody so you don't have to share. Do NOT look at the sun directly lest you blind yourselves. We used a filter for the hydrogen-alpha spectral line and thus had the added benefit of seeing protuberences at the edge of the sun's disc. The corona was surprisingly large too, considering the sun is 93 million miles away! NASA will be blogging it live of course, but if you get some good photos of the totality, be sure to blog them yourselves : expect to see this :-) CC, you are almost on the line of totality at 13:08 on 8-21-2017, so just drive to northern KC, take a few photos and blog them for us please :-) Comments (6) Sunday, August 6, 2017
Thin Man FailThis being Atom-Bomb week (Hiroshima 1945 on the 6th and Nagasaki 1945 on the 9th), I thought I'd blog a bit of early nuclear history.The Nagasaki bomb (August 9th 1945), called Fat Man, was an implosive design : a hollow sphere of fissile material had an outer shell of high-explosives. The segments of the outer shell were carefully timed to explode all at once, driving the fissile material (plutonium-239) into the centre where it achieved critical mass, exploding with 21 kilotons yield. The Hiroshima bomb (August 6th 1945), called Little Boy, was a gun-barrel design : a "bullet" of fissile material was fired along a barrel into a sub-critical mass of the same fissile material (uranium-235) where it achieved critical mass, exploding with 15 kilotons yield. Both designs need put the critical mass together very quickly to avoid a "fizzle" where the fissile material melts before contact. This was a problem for the first A-bomb design, the Thin Man. The Thin Man gun-barrel needed a muzzle velocity of 3000 fps, in order to put the critical mass of plutonium together quickly enough, which was close to the maximum achievable in 1944. This meant that the gun-barrel would need to be 17 feet long! There was only one aircraft in the Allied inventory that could carry a Thin Man unmodified: the British Avro Lancaster. Unneccessary US patriotism however, demanded the use of a Boeing B-29 Superfortress which had to be modified to carry a Thin Man by removing part of the main wing spar(sic!) and the oxygen tanks located between the B-29's two bomb bays. Not only this, but there were problems suspending the 8 ton bomb in the B-29 bomb bay. In several tests with dummy cases, the bomb pre-released before the bomb-doors opened, and the cases proved to be aerodynamically instable anyway. Furthermore, the spontaneous fission rate of their nuclear-reactor-bred plutonium was too high, meaning the A-bomb could have pre-detonated/fizzled too! So the Thin Man effort was scrapped but the design was used for the Little Boy which used uranium-235 instead as a fissile material and so the gun-barrel only needed to be 9 feet long, fitting better into a B-29. The casing was aerodynamically stable too and weighed only 4.5 tons, putting less strain on the release mechanism. Urban legend has it that Fat Man was named after Churchill and Thin Man after Roosevelt. Wikipedia provides a less glamourous naming though :-( Comments (2)
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Recent Writings
3 Neat Eclipse Photos :-) Great American Darkness Rare SG41 found! Hollywood Humour Eclipses Thin Man Fail Visit to Venice Lake Garda Mountains Jack-off-all-trades LBGT marriages legal Stagger McFly Aircraft Museum ecce libri : Hobbitus ille The HP warehouse Bode River scenery :-) May-Hem On turning 73 Time to die :-( Covfefe Learning to fly... In Memoriam : Klacks Pynchon turned 80 Oldtimer Meet in Boke May Day ;-) Blogroll Ain Bulldog Blog Badtux... Balloon Juice Cop Car Curmudgeonly... Earth-Bound Misfit Fail Blog Finding life hard? Hattie (Hawaii) Mockpaperscissors Mostly Cajun Not Always Right Observing Hermann Pergelator Rants from t'Rookery Yellowdog Grannie Archive 2017: Jan Feb Mar Apr May Jun Jul Archive 2016: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Archive 2015: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Archive 2014: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec This blog is getting really unmanagable, so I've taken the first 12 years' archives offline. My blog, my random decision. Tough shit; YOLO. Link Disclaimer ENGLISH : I am not responsible for the contents or form of any external page to which this website links. I specifically do not adopt their content, nor do I make it mine. DEUTSCH : Für alle Seiten, die auf dieser Website verlinkt sind, möchte ich betonen, dass ich keinerlei Einfluss auf deren Gestaltung und Inhalte habe. Deshalb distanziere ich mich ausdrücklich von allen Inhalten aller gelinkten Seiten und mache mir ihren Inhalt nicht zu eigen. This Blog's Status is Blog Dewey Decimal Classification : 153 FWIW, 153 is a triangular number, meaning that you can arrange 153 items into an equilateral triangle (with 17 items on a side). It is also one of the six known truncated triangular numbers, because 1 and 15 are triangular numbers as well. It is a hexagonal number, meaning that you can distribute 153 points evenly at the corners and along the sides of a hexagon. It is the smallest 3-narcissistic number. This means it’s the sum of the cubes of its digits. It is the sum of the first five positive factorials. Yup, this is a 153-type blog. QED ;-) Books I have written
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