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Eunoia
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Oh, and after the death of his old bulldog, Kosmo, he also has a new bulldog, Clara, since September 2018 :-)
Some of my bikes
My Crypto Pages 
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Thursday, February 29
Leap Day '24Early in the Roman empire they used a lunar calender of 365 days and so their seasons drifted off by about a day every 4 years. Meanwhile the Egyptians had tried to synchronise their calender with the flooding of the Nile river and had added a day every four years to keep in step. Then, in 46 BC, along came Julius Caesar and heard about this improved Egyptian calender and decided to adopt it by decree for the Roman empire. Since the Roman year started arbitrarily in March, he just added the extra day at the end of their year, whence the 29th of February as the leap day. This calender reform was named after him and became known as the Julian calender.The Julian calendar is a solar calendar of 365 days in every year with an additional leap day every fourth year (without exception) giving 365.25 days per average year. The Julian calendar is still used as a religious calendar in parts of the Eastern Orthodox Church etc. However the long term average for year length is 365.2422 days, which means the Julian calendar gains one day every 129 years. In other words, the Julian calendar gains 3.1 days every 400 years. So in October 1582, by which time the Roman empire had devolved into the Roman catholic church, the papal bull Inter gravissimas issued by Pope Gregory XIII, introduced the Gregorian calender as a modification of, and replacement for, the Julian calendar. This made the average calendar year 365.2425 days long, a better approximation to 365.2422 days. The Julian calender had drifted away from the equinox, so thursday 4 october 1582 was followed by friday 15 October 1582; remember this when calibrating your time machine ;-) BTW, the last country to adopt the Gregorian calender was Greece, as late as 1923 !!! The current rule for leap years is : "Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400." Actually, even this calender is still slightly off. It has an error of about one day per 3,030 years. This is because the Earth's speed of rotation is gradually slowing down, as the moon drifts away, which makes each day slightly longer over time. So in the 19th century the astronomer Herschel proposed a modification, "Make the year 4000, and multiples thereof, common instead of leap.", but this improvement still has not been officially adopted. So what events have happened on a leap day? Here are five. Do you have a birthday today? German law (BGB) states that after 18 years you legally become an adult just after midnight on February 28th. 55,000 Germans have a birthday today; worldwide about five million. Well, lass, that has changed over the years as the type of flying changed for me. So here are some old photos, hence excuse the lack of their quality.
I started off in the early seventies learning to fly Rogallo kites (glide ratio about 1:3) in the hills of Santa Monica (USA). Back in Germany I liked the Adler hangglider (ratio 1:8?) in
the hang-gliding school in the Sauerland hills.
So bought this yellow one, which I later crashed in a stall. Yellow is better seen by rescuers than green if you crash into the foliage :-(
Moving on to regular gliders/sailplanes, I found I was not very good at finding thermals. So the glider I most enjoyed was this pre-WW2 trainer, an SG38 (glide ratio 1:10).
You sit right out in the front, have NO instruments, and are catapulted off a hillside by a dozen friends running down the hill pulling a rubber rope ;-)
Moving on to powered planes, with about 200 hours of experience, at first I enjoyed aerobatics in a small biplane single-seater, a Pitts.
The Pitts can pull 9G and push -6, but I could only manage +6/-3G. Then I met SWMBO so needed more seats.
Meanwhile I had tried about 20 different types from MS880 via C172 to a Bonanza, but then settled for this 1969 PA28-140. Four seats (3 if I filled the long range tanks),
fixed undercarriage, fixed pitch prop, thinking "what isn't there can't go wrong". It served us well for a quarter century all around Europe :-)
Photo by his passanger Rosemary when I was formating on Anton's Bölkow 208.
I only flew twins if somebody else was paying - you need separate ratings for each twin type.
My favourite was Alan's Piper Aerostar, a quite fast 6 seater, which I preferred to the Cessna 310 and the MU2. Photo of the full IFR office.
Only disadvantages I found, the offset pedals and forward CG (Centre of Gravity).
Here's one kid's opinion . . .
BTW, here, headbangers are heavy metal music fans.
Comments(1)
This is a misapprehension. The Fat Man had a big external sheet steel casing, so that any possible machine gun bullets from a potential japanese Zero fighter plane
would not get through to damage the delicate atom bomb mechanism which depended upon retaining its 5 ft. diameter spherical shape. There is no atom bomb bigger than about 50 kilotons.
The bigger yield nukes are all hydrogen bombs (aka Thermonuclear bombs).
Then I realised most of my readers have never seen one, so here is a photo of the american B28 thermonuclear bomb.
Much smaller as you can see, thanks to design "advances". Fits on a fighter-bomber.
It has a yield upto 1.45 megatons afaik. I chose an (unclassified) photo with loading personnell for scale purposes.
I wrote about the largest possible nuke back in 2014.
The smallest nukes are socalled "suitcase" nukes which fit in a backpack or were used as an Honest John warhead.
Comments(1) Of course both ℼ and e are transcendental numbers, going on forever and never repeating themselves
so he needed a high precision to test this identity.
Now this supposed identity is almost, but not quite, true; so it took a week of debugging attempts for him to discover I was pulling his leg.
Using e.g.the calculator in Windowz I get 403,428793 for e6. And for ℼ4 +ℼ5 I get 403,428776 ;
a slight difference of about 4 parts in 100 million ;-)
Comments(1)
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Blog Dewey Decimal Classification : 153
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