Eunoia

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Stu Savory School report for Stu Savory
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 after the death of his old dog, Kosmo, he also has a new bulldog puppy, Clara, since September 2018 :-)


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Wednesday, January 22, 2020

Astronomically Stupid!!!

Sometimes I see cartoons etc which are so scientifically stupid and just plain WRONG that it makes me want to bang my head against a wall!

I don't know which amateur dilettante came up with this one, but it does take a prize for idiocy!

Let's take it apart and show the mistakes. We'll give the miscreant author the benefit of the doubt and assume his claim dates from 1991 not 2020. Why 1991? Well the moon landing was in 1969, and he wants to place a telescope to see the moon landing 22 light-years away and 1969+22=1991.

So if he built his "powerful telescope" in 1991 and then tried to place it in the desired position, even if he could transport it at the speed of light (the universal speed limit), the wavefront of the light from the moon landings would have moved on another 22 light-years. He would ALWAYS be 22 light-years behind that wavefront :-(

Now let's consider what his "powerful telescope" implies sizewise. Back in 1969 we didn't have telescopes powerful enough to even see the moon landing from Earth. And the Moon is only 1¼ light-seconds away from the Earth. We didn't have them by 1991 and we don't even have them today! Not even diffraction-limited telescopes would be able to see the moon-landing from Earth unless they were absolutely huge, perhaps miles and miles across; you do the math on the size of their Airy disc.

This is a picture of Saturn, which is about 64 light-minutes away from Earth at their closest approach. It was taken with an amateur's 8-inch aperture reflector scope. The image quality was seeing-limited (as are all photos from the surface) but I got a factor 4.5 improvement in signal/noise ratio (image quality) by stacking 20 different 30-second exposures on top of one another. An 8 inch mirror gave me a useful magnification of only 8*50=400. Now think of the size of Eagle compared with the size of Saturn, much less than a pixel here :-(

Now the picture above of Saturn is of much better quality (aka resolution) because it was taken by the Cassini spaceship from quite close to Saturn (light-seconds not 64 light-minutes), you still can't see Eagle-size rocks in the rings.

Cassini also took a picture looking back from Saturn's orbit, showing Earth and the Sun. Our Moon is not even visible.

So if this is looking back from just over a light-hour away, and you can't even see our Moon let alone the Eagle on it, then how large a telescope would you have needed to see Eagle from a light-hour away? Now scale that up (by 192700) to 22 light-years away. Impossible!

For more exposures about bad astronomy, I refer you to Phil Plait, a professional astronomer.


Sunday, January 19, 2020

Megxit

The trash press insist on keeping us up to date about the UK's royal family squabble.

It seems that Harry and Meg will go from HRHs to TCL (Their Common Lownesses), get NO public cash, have to repay the £2.4 Mio that was invested in rebuilding Frogmore Cottage (for which they will now have to pay rent), may no longer represent the Queen, make no military appointments (so Harry has to give back all his uniforms, except perhaps that Nazi one(?)), no longer be Captain General of Marines, Hon Air Commandant, Commodore-In-Chief and Youth Ambassador, return the fake medals, etc etc.

Inconsistent with this, it seems they retain the titles Duke & Duchess of Sussex, so it is unclear (to me) whether their website can retain the https://sussexroyal.com/ URL. But who cares?

Moving to Canada may teach them how to say "Sorry!", but in two weeks (the Brexit date) Canada may no longer recognise their passports which still bear the misleading claim "European Union"?

All of this and they will be getting more rather than less papparazzi :-(
I give them two years before Meghan files for divorce.

Comments (1)
Ed (USA) sent this cartoon :-


Thursday, January 16, 2020

U.S. Aircraft Carriers

The USA is a very belligerent nation and has in fact been at war for over 90% of its history :-( The word belligerent comes from the Latin belligenere meaning "waging war".

But because the USA is far away from most other countries and its air-superiority fighters and ground-attack fighter-bombers have relatively short ranges, it needs aircraft carriers to transport them to their war-zones. Currently the US has 11 of them in service and 4 more in the pipeline.

There are two classes in current use, the Nimitz class and the Gerald R. Ford class. Apart from the (9th) reuse of the name Enterprise, many of these supercarriers are named after US presidents, not very enterprising ;-)

But one was named after a US king!

Did you know that the USA once had a king? I don't mean King George or one of the other older Brit kings; this was in the 20th century! In fact there was one person - the only person - who served as both Vice President and as President of the USA (but was never elected to either office!) who was born with the surname King.

Leslie Lynch King Jr. was otherwise known as Gerald R. Ford after whom the newest class of U.S. aircraft carriers is named. Of the Nimitz class, seven (out of 10) were named after US presidents. Two of the Gerald R. Ford class have been completed, both named after US presidents. If there is ever one to be named after Donald J. Trump (the J stands for Jenius, he told us) it will be subject to a deck redesign and will look like this :-;

Pax vobiscum!

Comments (1)
Cop Car wrote "Enterprise : The Big "E" holds a warm place in some of our hearts. Commissioned in 1961, she was the first nuclear-powered US aircraft carrier and was active during my years in the US Naval Reserves (1980-1986). The new Enterprise (Gerald Ford class) won't enter the fleet for nearly 10 years, at best. I lament that the US spends so much on armaments and fighting troops (and, especially, on actual fighting); but OTOH, many non-US citizens have, over the years, wanted/expected the US to police the world. Those days are probably over since Trump began his reign. With good reason, we are no longer seen as dependable partners." I wish we could have Obama back again; that was one respectable dude!


Tuesday, January 14, 2020

No memory lockout :-(

My memory is getting worse :-(

We were going to the MC monthly party, SWMBO, the dog and I. They had already left the house, headed for the carport, when I pulled the front door of the house closed behind me. Only to discover the keyring with car-key and house-key were still in the hook in the house :-( Oh, shit! I'd forgotten the key and so locked us out of house AND car!

While SWMBO was having a grand fit of fury at my incompetence, I was trying to think what to do. Good friends have our spare key, so call their mobile phones as they are going to the same party. Their phones were turned off as they were going to a party :-( So I called a cab to take us there too. When the cab arrived (after we'd sat 20 minutes in the cold, waiting), he refused to take us because we had the dog with us :-(

So we called other friends at the same party until we found one whose mobile was turned on and asked to talk to the couple with our spare key. Said lady then generously drove back to bring us our spare house key. Situation saved at the cost of waiting an hour in the cold. And I owe her drinks next time, when she is not the designated party driver! Thankyou! It was my bad!

We have this biker spare-key-swapping habit from our long motorcycle trips (where we've never lost a key). But it paid off this time. I'm not someone who leaves a house-key under the doormat like some folks in the village!

But I need to do something to improve my memory as I get older.
Follow checklists maybe, which I always preached as a flying instructor.

What's your emergency plan?

Comments (4)
Doug (Canada) wrote "I can so relate [to that last box]" :-(
Jenny (Ibiza) punned "Here are some old memories for you ;-)"

Cop Car wrote " I bought a little house in December 1977, during which time we were experiencing snow/sleet/blowing weather for the whole month. In addition, I was working a temporary assignment at the company's division that was clear across town. Great timing! In moving my stuff from my apartment the first day, I managed to lock myself out. (BTW, the previous owners had about four sets of locks and chains on the front door.) I was so infuriated that I took the tire iron out of my trunk and pretty much destroyed the frame of the front door to get inside. After unloading my carload of stuff, I went to the hardware store to purchase three sets of heavy-duty deadbolts. After rebuilding the door frame and installing the deadbolts I never again locked myself out. Since that day, much to Hunky Husband's dismay, I've never lived in a house that did not have deadbolt locks. And I've never been locked out, again; although (of course it had to happen), HH locked himself out when he went for his run one day - while I was at the eye doctor's.
My recovery plan is to set fire to the house out of which I am locked!"
I didn't recognise the term "deadbolt" (...separated by a common language...), but after reading the Wikipedia article, see that we have the same kind of locks over here. Your recovery plan is hilarious, sounds like Trump's Iran plan :-(
Schorsch (D) asks "So where was your lockpicking picking kit you've blogged about before?" Inside the house, of course :-(


Friday, January 10, 2020

Factorial fun!

Time for sum(!) more maths fun.

Recently, my old friend John (UK) whom I've known for over 55 years, opined that I was some sort of polymath (that's someone who can parrot algebra etc ;-). Nice complement/compliment, not sure I agree. Another old friend Derek (Canada) - we all went to university together - saw the syllable "math" and ran with it, sending me four proofs that factorial zero = one. I maintain that you can't prove it, merely define it to be so.

So let's do this. Factorial N can be defined as the product of all positive integers up to N. So factorial 5 = 1*2*3*4*5 = 120. But this doesn't cover factorial zero, so we need a different definition. Most programming courses will use factorial N as an example for teaching recursion, saying that recursively factorial(N) = N * factorial(N-1). Reversing the sequence shown above factorial(5) = 5*4*3*2*1 =120. Or :- factorial(5)=5*factorial(4), where factorial(4)=4*factorial(3) and factorial(3)=3*factorial(2) and factorial(2)=2*factorial(1) and factorial(1)=1*factorial(0) using the recursion shown above and therefore factorial(0)=1 just to make this definition consistent. QED.

You could use a different definition for factorial N. It is the number of different ways you can place N items on a line. So with three items, A,B, and C you could place them as ABC, or ACB, or BAC or BCA or CAB or CBA. So factorial(3) is 6 because there are 6 different ways to place 3 items in a line. Factorial(2) is 2 because there are 2 different ways to place 2 items in a line (AB and BA). Factorial(1) is 1 because there is only one way to put one item on a line, and similarly Factorial(0) is 1 because there is only one way to place zero items in a line :-)

I have another anecdote about factorials. About 35 years ago I was working with Prof. Wolfgang K. Giloi (R.I.P these 10 years) on efficient algorithms. He asked his students what was the most efficient sorting algorithm (Quicksort, imho) and which was the most inefficient. The latter they thought to be BubbleSort. However, I explained that there is an even more inefficient sorter: ChanceSort. This just looks at an array and, if it is already sorted, stops. Otherwise it shuffles the array at random and tries again. And again. And again. Now since there are Factorial(N) different ways you can place N items in the array, the average runtime will be Factorial(N)/2. Terrible!

Now I'm going to skip talking about factorials of fractions (example : factorial(½) = root(Pi)/2 because that would be getting into complex territory, so here are some more general maths jokes I found on the web :-

In that last one, little children show us our limitations. Here's one of mine : I've been trying for the last twelve years to prove that every even number is the sum of two primes, without success. Why? There's a prize of one million dollars for the first person to prove that :-) It's called Goldbach's conjecture and computers have shown it holds for all the even integers up to 4*1018, but that's not a proof it holds for ALL of them :-(

Comments (3)
Derek wrote "Your related episode ... prompted me to query why factorial 0 is equal to one, recalling that it is involved in the series for the base of natural logs i.e. e = 1/0! + 1/1! + 1/2!...........etc." Yes, Euler's number is the sum of the reciprocals of the integer factorials; neat, huh? :-)
Jenny (Ibiza) sent this pun :-


Carol (UK) wrote "Off Topic : Wolfgang Dauner died on friday. I know you were a fan." He was 84, afaik. RIP.


Monday, January 6, 2020

Going to Mars

Every couple of years, the orbits of Earth and Mars around the sun are such that the two planets are quite close together. That means that there is an elliptical orbit for lobbed spacecraft so that the zero-g transit time is "only" six to ten months. Quite close ;-) And that happens this year, so there are currently four missions planned to send spacecraft to Mars.

NASA already has four rovers there, Curiosity, Opportunity, Sojourner and Spirit. Now they are planning a fifth - a twin of Curiosity - to be launched in the july/august timeframe. It too will search for traces of life on Mars.

ESA (the European Space Agency) - in cooperation with Russia - will be sending a rover named after Rosalind Franklin who helped discover the DNA double helix (but didn't get a Nobel prize because she died early (at 37) of ovarian cancer). This rover will be landing where there used to be a sea and will there bore a two-meter deep hole in the search for any subterranean(?)/submartian(?) remains of sea-life, possibly microbial.

The Chinese mission "Yinghuo 2" (= Firefly 2) consists of an orbiter, lander and a rover (four separate spacecraft). The rover will be searching for water-ice in the martian rocks.

The fourth mission is by the United Arab Emirates and is called Hope. It is an orbiter only, a landing is not planned. Its job is to analyse the martian atmosphere. I just hope that all the landers (and the orbiters, should they crash) are biologically 100% sterile and so do not pollute Mars with any terran lifeforms (bacteria, virii) !

You know, if any aliens from another solar system arrived in our solar system and investigated Mars as the first planet in within the habitable zone, they would report back home that Mars is entirely inhabited by robots ;-)

All this enthusiasm for Mars reminds me of my own enthusiasm as a small boy for Barsoom, a series of 7 novels by Edgar Rice Burroughs which he wrote about 100 years ago. When mankind sends a manned spacecraft to Mars, it should imho be named Barsoom 1 and the (single?) crew member should imho change his name by deed poll to "John Carter" ;-)

Comments (1)
Jenny (Ibiza) sent this cartoon :-


Yes, Jenny, and Trump is wagging the dog (= impeachment distraction) while Iranian generals name themselves after their favourite attack methods : the assassinated general was called Gas 'em.


Friday, January 3, 2020

Holiday avian dining

How do you know someone is vegan, without seeing what they eat? They will tell you. Over and over again. At great length. Like listening to a Jehovah's Witless proselytizing. What incessant bores they are!

So by way of revenge, I am going to tell you what we ate over the holidays. Birds. We ate birds. Two of them. Either by countryside tradition or because our local butcher only offers an avian diet around Xmas time.

Back in 2017, we ate a pheasant which SWMBO had shot (she's the one with the hunting license, I'm just the pheasant plucker, as you all know ;-) ). Here are the Xmas 2017 photos. I still think that pheasant is the most tasty bird to eat. 2018 we enjoyed ostrich schnitzel; a little on the dry side, there being very little fat on them. Last year we ate duck on Xmas eve, delicious and nicely crispy. So Xmas day it was duck leftovers, eaten cold, but still quite tasty. On Boxing day we ate goose (thighs), a darker meat, not so crispy and a bit fatty. So next day it was goose leftovers, microwaved warm, still good.

Do not eat swan! They are greasy and oily and hard to chew. There are still some restaurants in the north of Germany which have swan on the menu. Curiosity got the better of me (sadly), as in the UK you are not allowed to eat swan. All the swans in the UK belong to HM the Queen and she is not going to let commoners eat them. Just as well. Avoid eating swan! Greasy & chewy :-(

So did you eat any birds over the holidays?

Comments (1)
Doug (Canada) wrote "I ate home made shepherd's pie (beef not lamb-can't stand lamb) both days." So if I served you lamb, you'd have something to beef about? ;-)


Wednesday, January 1, 2020

Valid_Dated

So here we are at Hogmanay+1; welcome to the New Year. Now we just have to remember to write 2020 each time, validating the time and date which we'll sometimes get wrong at the start of a new year.

Years ago, I was tasked with writing software to check times and dates as they were being entered to a database. Easy, I thought. 24 hours (0-23), 60 minutes (0-59), and 60 seconds (0-59). Turns out to be harder than I'd imagined. Sometimes there are 61 seconds in a minute, due to leap seconds. Leap seconds can be introduced in UTC at the end of the months of December or June. Because the Earth's rotation speed varies in response to climatic and geological events, UTC leap seconds are irregularly spaced and unpredictable, but usually 6 months notice is given. So my SW had to access https://datacenter.iers.org/data/latestVersion/16_BULLETIN_C16.txt to see when the next leap-sec was due, as only then were 61 seconds valid.

Next issue was to validate the date. We all know the table of short vs. long months and the rule for a leap year. But that's not the whole game. The sequence of dates depends on where you were at the time. On December 23, 1994, the Republic of Kiribati announced a change of time zone for the Line Islands, which are on the International Date Line, to better align them with the increasingly important trade partner (Australia) instead of the USA. So the day after december 29th was december 31st for them. 30/12/94 was an invalid date there!

If my SW was to be used for historical dates, it would have to cope with the year zero problem. The Gregorian calendar jumps from 1 BC to 1 AD, there is no year zero, they assume Jesus aged very quickly ;-) However, there is a year zero in astronomical year numbering (where it coincides with the Julian year 1 BC) and in ISO 8601:2004 (where it coincides with the Gregorian year 1 BC), as well as in all Buddhist and Hindu calendars. This leads to the idea that the date can depend on your religion too! Help!!! And on the region you lived in : February 30 was a real date in Sweden in 1712. As if that wasn't enough, different countries (as they were bordered back then) changed over from the Julian to the Gregorian calendar in different years, not all following the Pope's orders. So it's religion AND region too.

The problems happen this week too. Monday 30/12/2019 is listed in my business calendar as starting Week 1 of 2020. Kinda confusing :-(

Whatever, here's wishing you all a healthy and happy New Year!

Comments (3)
Iain (UK) wrote "The BBC has a video about current non-Gregorian calendars online today here." Such a variety!
Carol (UK) asks "Is January 1st a public holiday in Germany as in Scotland?" Yes. And local Catholics celebrate Jesus brithday then too. A brithday is the day a child is circumsized and assigned a name; eight days after birth in jewish tradition. So strictly speaking, Jesus was not born in a manger; a nameless child was. Since His foreskin was the only part that didn't ascend into heaven (having been cut off), centuries later there was a big squabble between the cathedrals at Chartres (France) and Canterbury (England) as to who had the One True Relic in their golden chalice! Religious nuttery ;-)
Pergelator wrote "A while back I wrote a computer program for a data logger. Keeping track of the time and date was kind of important, so I spent some time on it. I used a 32-bit integer to count the seconds. A signed integer will get you 50 years. Surely all these devices will have become obsolete in 50 years and will be replaced, won't they? 20 years later I am not so sure." Yup. The German Air Force still uses a system I wrote for them around 1970 :-)


Link to the previous month's blog.
Recent Writings
Astronomically Stupid
Megxit
U.S. Aircraft Carriers
No memory lockout :-(
Factorial fun
Going to Mars
Holiday avian dining
Valid_Dated
Good Omens & Puckoon
Khoroshevskoye Shosse
Winter solstice
Torn ligament :-(
Paraskevidekatriaphobia
Custom Bike Show
PISA results worsen
Hundertwasser brewery
Free Lunch :-)
In Germany's oldest Inn
A History of Economics
The Day the Wall fell
Transit of Mercury
Harley Outfit restored!
Halloween costume 2019
Harry and Meghan ;-)
Fall fungi
Mathematical mega-mug

Blogroll
Ain Bulldog Blog
All hat no cattle
Badtux...
Balloon Juice
Cop Car
Digby's Hullabaloo
Earth-Bound Misfit
Fail Blog
Finding life hard?
Greg Laden
Hackwhackers
Infidel753
Mockpaperscissors
Mostly Cajun
Observing Hermann
Pergelator
Starts with a Bang
Travels With an Alien
Yellowdog Grannie

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This blog is getting really unmanagable, so I've taken the first 12 years' archives offline. My blog, my random decision. Tough shit; YOLO.
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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 : F?r alle Seiten, die auf dieser Website verlinkt sind, m?chte ich betonen, dass ich keinerlei Einfluss auf deren Gestaltung und Inhalte habe. Deshalb distanziere ich mich ausdr?cklich 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 ;-)
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