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Saturday, December 31, 2016

What's A Leap Second?

Screenshot of the UTC clock from during
 the leap second on December 31, 2016.
Every now and then a leap second is added to Coordinated Universal Time (UTC) in order to synchronize clocks worldwide with the Earth's ever slowing rotation.

Atomic Time vs. Universal Time - two components are used to determine Coordinated Universal Time (UTC):

International Atomic Time (TAI): A time scale that combines the output of some 200 highly precise atomic clocks worldwide, and provides the exact speed for our clocks to tick.

Universal Time (UT1), also known as Astronomical Time, refers to the Earth's rotation around its own axis, which determines the length of a day.

Here're some excerpts from WhatIf's excellent explanation - go there and read the whole thing:
Half a billion years ago (when the Earth was 4 billion years old, instead of 4.5), each day was 22 hours long instead of 24. The day has gotten longer because of tidal forces from the Moon.
Loosely speaking, here’s how tidal drag works: The Moon’s tides raise bulges in the Earth, but the Earth’s rotation moves those bulges out of line with the Moon. The Moon’s gravity tries to tug the bulges back into line, which exerts a twisting force on the Earth, slowing it down.
Strangely, the Earth is actually not slowing down as much as you’d expect from tidal drag. The biggest reason for the discrepancy is that during the last ice age, the continents were pushed down by the weight of the glaciers, and they’re still springing back into place. This has the effect of shifting mass toward the poles, closer to the axis of rotation: 
At the moment, each day is about 0.8 milliseconds longer than the 86,400 seconds it needs to be to avoid adding leap seconds.
This difference fluctuates over time based on weather and other effects (it’s actually shortened a bit since the early 1990s), although in the long run, it will definitely get larger as the Earth slows.
If we wanted to get rid of leap seconds, we’d need to keep the Earth spinning at a more constant rate. This means speeding up the Earth and shortening each day by about 0.8 milliseconds. 

This is a tough problem. Here are a few things that won’t work:

Spinning counterclockwise in a chair. It temporarily alters the Earth’s rate of rotation, but not enough to matter.

Putting rocket engines on the Equator. This won’t work because the exhaust would go into the atmosphere, which transmits the force back to the ground as wind drag—it’d be like making a bike go forward by pushing on the handlebars. If the engines were somehow mounted above the atmosphere, they’d be able to slow the Earth, but not by enough to accomplish our goal.

Triggering big earthquakes. This can alter the length of the day, but even those aren’t big enough to make a difference.

In the end, there’s only one solution: Hitting the Earth with asteroids.
More science, from
A normal day has 86,400 seconds, but in the atomic time scale 1 second is not defined as one 86,400th of the time it takes Earth to rotate around its axis but rather as the time it takes a Cesium-133 atom at the ground state to oscillate precisely 9,192,631,770 times.

The advantage of this definition is that it is extremely precise: atomic clocks deviate only 1 second in up to 100 million years. On the other hand, the Earth's rotation, which is expressed by the time standard UT1, is far less reliable. It slows down over time, which means that days get longer. On average, an Earth day is about 0.002 seconds longer than the daily sum of the 86,400 seconds measured by the atomic clocks. This makes for a discrepancy between TAI and UT1 of around 1 second every 1.5 years.
Leap seconds are added to our clocks (UTC) so this discrepancy does not get too large over time and the time we use is synchronized as much as possible with the Earth's rotation.
When the difference between UTC and UT1 approaches 0.9 seconds, a leap second is added to UTC and to clocks worldwide. By adding an additional second to the time count, our clocks are effectively stopped for that second to give Earth the opportunity to catch up with atomic time.

More at TimeandDate and WhatIf.

Friday, December 30, 2016

New Year's links

Advice from 1862: How to Tell Your Fortune for the New Year.

List of lists: the lists of top 2016 science stories from 24 different sources.

Dave Barry's 2016 Year In Review. Previous such columns are available here.

How (Not) to Celebrate the New Year: Advice from 700 AD (or thereabouts).

Strange New Year traditions around the world.

Some links to avoid becoming philogrobolized:
Your Complete Guide to the Science of Hangovers.
Infographic on the Anatomy of a Hangover.
Hangover Cures From Famous Heavy Drinkers.
5 Really Strange Ways to Cure a Hangover.
Scientists Find a Way to Cut Wine Hangovers.
Dark Liquor Makes For Worse Hangovers.
How to Cure a Hangover.
According to a study in the Journal of Food Science, the amino acids and minerals found in asparagus extract may alleviate alcohol hangover and protect liver cells against toxins.

Why We Sing Auld Lang Syne on New Year’s Eve, and here's Mark Steyn singing and explaining What Are You Doing New Year's Eve?

Eat your heart out, New York: Boise, Idaho drops a giant potato downtown on New Year's Eve.

Sunday, December 25, 2016

Merry Christmas!

Nativity, Gerard van Honthorst, 1622
For unto Us a Child is born
Unto Us a Son is given
And the government shall be upon His shoulder
And His name shall be called Wonderful, Counsellor,
The mighty God, The everlasting Father, The Prince of Peace.

May your Christmas be filled with joy.

Saturday, December 24, 2016

Christmas Eve links

Please accept with no obligation, implied or explicit, my best wishes for an environmentally conscious, socially responsible, low-stress, non-addictive, gender-neutral celebration of the winter solstice holiday, practiced within the most enjoyable traditions of the religious persuasion of your choice, or secular practices of your choice, with respect for the religious/secular persuasion and/or traditions of others, or their choice not to practice religious or secular traditions at all. I also wish you a fiscally successful, personally fulfilling and medically uncomplicated recognition of the onset of the generally accepted calendar year 2017, but not without due respect for the calendars of choice of other cultures whose contributions to society have helped make America great. Not to imply that America is necessarily greater than any other country nor the only America in the Western Hemisphere. Also, this wish is made without regard to the race, creed, color, age, physical ability, religious faith or sexual preference of the wishee.

Rare vintage video footage: Christmas in the 1920s.

In the Christmas In Other Cultures category, here's a Klingon Christmas Carol. Also, how to have a British ChristmasSweden's bizarre tradition of watching Donald Duck (Kalle Anka) cartoons on Christmas Eve, Strange Christmas Traditions Around the World, and why Japan is Obsessed with Kentucky Fried Chicken on Christmas.

Holiday Hairstyles Sure To Shock Santa.

At Christmas, this town builds a Giant Yule goat and then torches it.

Great Literary Christmas Tales That Aren’t A Christmas Carol.

Virginia O'Hanlon, of Yes, Virginia, there is a Santa Claus fame, was asked about that letter for the rest of her life.

The real history of ‘Rudolph the Red-Nosed Reindeer’ - it all started with a Montgomery Ward marketing campaign in 1939.

Little Drummer Boy, sung by David Bowie and Bing Crosby.

Supercut of movie Santas.

Here's a Christmas light version of Santa Claus urinating on ISIS sign.

10 Important Facts About A Christmas Story's Leg Lamp. Related: Ralphie teamed up with Flash Gordon in a deleted scene from A Christmas Story.

ICYMI, Wednesday's links are here, and include printable Star Wars snowflake templates, all about the winter solstice, and the classic drunken fruitcake recipe.

Wednesday, December 21, 2016

Wednesday links

December 21 is the winter solstice, the first day of winter, and the shortest day of the year. Here are science, history, and short video explanations of the celestial mechanics involved, plus descriptions of the concurrent celebrations of Saturnalia and Halcyon Days.

How The World Looked When Jesus Was Born, According to Roman Geographers.

A collection of downloadable templates for Star Wars snowflakes.

Classic Christmas drunken fruitcake recipe: Check the whiskey. Pour 1 level cup and drink. Repeat.

The 1914 Christmas truce.

The Origin of the Myth of the Poisonous Poinsettia. Related, why we kiss under the mistletoe and how the plant got that strange name (spoiler - it literally means "dung twig").

ICYMI, Friday's links are here, and include advice from ~1200 on how to survive the winter (don't forget to lay off the purging and blood-letting, and keep your hands and feet covered in wolf grease), the complicated history of humans and cats, an island where donkeys wear pajamas, and a map of the entire internet as of 1973, on one sheet of paper.

Friday, December 16, 2016

Friday links

Here, on one sheet of paper, is a map of the entire internet as of 1973.

The Island Where Donkeys Wear Pajamas.

Advice from c. 1200: How to Survive the Winter. Don't forget to lay off the purging and blood-letting, and keep your hands and feet covered in wolf grease.

Humans and Cats Have a Strange, Complicated History.

Digital Incarceration: The Finger Pillory.

ICYMI, Wednesday's links are here, and include lots of ugly Christmas sweaters (and DIY instructions for making your own), how animals cope with cold, debunking Kwanzaa, and a 1562 map of America showing the homes of giants, mermaids, dragons and cannibals. Also, T'was the Overnight Before Christmas: the merry tale of how air cargo deregulation led to Amazon.

Thursday, December 15, 2016

A movie is being made about Dunkirk - here's the trailer

The evacuation of large elements of the British and French armies from Dunkirk (wiki) on the French coast, which took place during the period from May 26 through June 4, 1940, followed their defeat by the German blitzkrieg that overwhelmed France during the early months of World War II. The sudden German attack through Belgium on May 10 had quickly rolled up the French and British left wing and surrounded it in a small enclave on the English Channel opposite Dover. 

In a largely improvised but brilliantly executed maritime operation that mustered both the Royal Navy and civilian small craft of every kind, nearly 340,000 British and French troops - nearly 90 percent of those invested - were ultimately withdrawn, despite incessant German armored and air attacks.

Dunkirk was, of course, the inspiration for Winston Churchill's "We shall fight on the beaches...we shall never surrender" speech:
We shall not flag or fail. We shall go on to the end. We shall fight in France, we shall fight on the seas and oceans, we shall fight with growing confidence and growing in the air, we shall defend our island, whatever the cost may be, we shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills; we shall never surrender.

More on Dunkirk here, including a contemporaneous newsreel.

Excellent cartoon: "The Talk", because if you don't explain quantum computing to your kids, someone else will

Scott Aaronson and Zach Weinersmith at SMBC (Saturday Morning Breakfast Cereal):

Wednesday, December 14, 2016

Wednesday links

Lots of ugly Christmas sweaters, instructions for making your own, plus ugly Christmas sweater suits, and here's how to make Ugly Sweater Ornaments.

CIA Declassifies Maps from 75 Years of Surveillance.

T'was the Overnight Before Christmas: The Merry Tale of How Air Cargo Deregulation Led To Amazon. Related (by the underlying poem): T'was the Night Before Kwanzza, and more of Kathy Shaidle's Kwanzaa-debunking collection

ICYMI, Monday's links are here, and include Mother Teresa's meeting with then-NYC Mayor Guliani to lobby for a parking permit, the pre-Seinfeld origins of Festivus, Teddy Roosevelt's impact of football, and a new Guinness World Record-setting Rube Goldberg machine that takes 412 steps to light a Christmas tree.

Monday, December 12, 2016

Monday links

Before Seinfeld: The Origins of Festivus.

ICYMI, Friday's links are here, and include (without limitation) lots of really bad nativity sets, the history of the chicken dance, Pretend to Be a Time Traveler Day, and how McDonald's got started.

Saturday, December 10, 2016

New Guinness record-setting Rube Goldberg machine takes 412 steps to light a Christmas tree

A new Guinness world record-setting Rube Goldberg machine (wiki) just in time for Christmas - watch the municipal Christmas tree in Riga, Latvia, get switched on by a process requiring 412 steps and 10 minutes to complete (the video is condensed), bettering the previous record of 382 steps achieved in Hungary back in April 2015. The company Scandiweb sponsored the record-setting chain reaction that Guinness has enshrined as the World's Largest Rube Goldberg Machine

The principle of a Rube Goldberg machine (wiki) is to complete a simple task in the most complicated way possible. This attempt featured a diverse range of devices including traditional parts like wheels, levers and balls, as well as more unusual items like a fan and coffee maker.
The finale was initiated by a sound meter that was triggered by the shouts and screams of the guests.

Sort of related video: Rube Goldberg's Passover Seder

Friday, December 9, 2016

Friday links

A selection of weird nativity sets.

The Popular Victorian Clubs That Yearned To Fill Europe With Hippos.

A potential boon for DUI defense lawyers: Hand Sanitizer Can Cause a False Positive Breathalyzer Test.

ICYMI, Wednesday's links are here, and include cooking with early microwave ovens, huge historical natural disasters, all about St. Nicholas of Myra (aka Santa Claus), the anniversary of Pearl Harbor, and the only person ever hit by a meteorite.

Thursday, December 8, 2016

Pretend To Be A Time Traveler Day

Pretend To Be A Time Traveler Day was created in 2007 by a now defunct (as far as I can determine, anyway) conglomerate of webcomics called Koala Wallop*. Here's Wired at the time:

Saturday, December 8th has been declared "Pretend to be a Time Traveler Day."  The whole idea is to pretend for the day that you are a traveler from a different time – except that, of course, you can’t actually *tell* people you’re a time traveler, because they’ll think you’re crazy.  There are, of course, options as to how a traveler from a certain other time might act:

Utopian/cliché Future –

If the Future did a documentary of the last fifty years, this is how badly the reenactors would dress. Think Star Trek: TNG or the Time Travelers from Hob. Ever see how the society in Futurama sees the 20th century? Run with it. Your job is to dress with moderately anachronistic clothing and speak in slang from varying decades. Here are some good starters:

– Greet people by referring to things that don’t yet exist or haven’t existed for a long time. Example: "Have you penetrated the atmosphere lately?" "What spectrum will today’s broadcast be in?" and
"Your king must be a kindly soul!"

– Show extreme ignorance in operating regular technology.  

Dystopian Future

This one offers a little more flexibility. It can be any kind of future from Terminator to Freejack. The important thing to remember is dress like a crazy person with armor. Black spray painted football pads, high tech visors, torn up trenchcoats and maybe even some dirt here or there. Remember, dystopian future travelers are very startled that they’ve gone back in time. Some starters:

– If you go the "prisoner who’s escaped the future" try shaving your head and putting a barcode on the back of your neck. Then stagger around and stare at the sky, as if you’ve never seen it before.

– Walk up to random people and say "WHAT YEAR IS THIS?" and when they tell you, get quiet and then say "Then there’s still time!" and run off.

– Stand in front of a statue (any statue, really), fall to your knees, and yell "NOOOOOOOOO"

– Stare at newspaper headlines and look astonished.

– Take some trinket with you (it can be anything really), hand it to some stranger, along with a phone number and say "In thirty years dial this number. You’ll know what to do after that." Then slip away.

The Past

This one is more for beginners. Basically dress in period clothing (preferably Victorian era) and stagger around amazed at everything. Since the culture’s set in place already, you have more of a template to work off of. Some pointers:

– Airplanes are terrifying.  Also, carry on conversations with televisions for a while.

– Discover and become obsessed with one trivial aspect of technology, like automatic grocery doors. Stay there for hours playing with it.

– Be generally terrified of people who are dressed immodestly compared to your era. Tattoos and shorts on women are especially scary.

If anyone gives this a try, report back to the class and let us know how it went. ;-)

I think this is one of the original comics - larger version here.

Related: What’s the Best Item to Carry With You During Time Travel?

Wednesday, December 7, 2016

Wednesday links

A day that will live in infamy: It's the anniversary of the attack on Pearl Harbor.

How Civil War Soldiers Gave Themselves Syphilis While Trying to Avoid Smallpox.

Microwave Memories - cooking with early microwave ovens

December 6 was the feast day of St. Nicholas of Myra, aka Santa Claus.

ICYMI, Monday's links are here, and include the end of prohibition, why, when facing predators, male monkeys do whatever the females tell them to do, who poisoned the Goebbels children in Hitler's bunker, and lots of awkward Christmas photos.

Monday, December 5, 2016

Monday links

The precursor to the war on drugs: on December 5th, 1933, prohibition in the United States of America came to an end.

Murder in Hitler's Bunker: Who Really Poisoned the Goebbels Children?

The stories behind Fahrenheit and Celsius.

It's that time again - lots of awkward Christmas photos.

11 Real-World Forests That Look Like They're Straight Out Of A Fairytale.

ICYMI, Friday's links are here, and include plant geometry, DIY vaginal steam-cleaning, competitive eating history, the medical dangers of kissing, and the anniversary of the Monroe Doctrine.

Sunday, December 4, 2016

December 6 is the feast day of St. Nicholas of Myra, aka Santa Claus

His eyes - how they twinkled! His dimples: how merry,
His cheeks were like roses, his nose like a cherry;
His droll little mouth was drawn up like a bow,
And the beard of his chin was as white as the snow;

The stump of a pipe he held tight in his teeth,
And the smoke it encircled his head like a wreath.
He had a broad face, and a little round belly
That shook when he laugh'd, like a bowl full of jelly. 

~Clement C. Moore (1779-1863) ("A Visit from St. Nicholas," excerpt*) 

The giver of every good and perfect gift has called upon us to mimic God's giving, by grace, through faith, and this is not of ourselves.

~ St. Nicholas of Myra (attributed) 

Once again St. Nicholas Day
Has even come to our hideaway;
It won't be quite as fun, I fear,
As the happy day we had last year.
Then we were hopeful, no reason to doubt
That optimism would win the bout,
And by the time this year came round,
We'd all be free, and safe and sound.
Still, let's not forget it's St. Nicholas Day,
Though we've nothing left to give away.
We'll have to find something else to do:
So everyone please look in their shoe!?

~Anne Frank (1929-1945) (The Diary of a Young Girl, 6 December 1944) 

Give all thou canst; high Heaven rejects the lore
Of nicely-calculated less or more.

~William Wordsworth (1770-1850) ("Tax Not the Royal Saint") 

December 6 is the feast day of Saint Nicholas of Myra (270-343) (wiki), perhaps better known in his latter-day guise as Santa Claus. Born to Greek Christian parents in Palmyra in southern Anatolia, Nicholas was renowned for his great piety at an early age and eventually became the bishop of nearby Myra in what is now Turkey.

St. Nicholas saving the three poor girls and their father
He is known to have attended the Emperor Constantine's First Council of Nicea (325), where he took a strong stand against Arianism, but very little else is certain about his life. On the other hand, a rich body of legends has grown up around his name, largely for working many miracles and his life-long propensity for gift-giving.** Most famously, he is said one night to have thrown three small bags of gold through the window of a poor man as doweries for his three daughters, thus saving them from a life of prostitution.***  On another occasion, he abated a fearsome storm at sea, and thus has been adopted as the protector of sailors and fishermen. 

In 1087, half of his remains were purloined from Myra by sailors from southern Italy and enshrined in the basilica of San Nicola in Bari, where they remain today, the object of great veneration. (The other half of his bones somehow found their way to Venice.) Generally portrayed with his bishop's robes and regalia, Saint Nicholas is one of the most popular saints in both the Catholic and Orthodox traditions and is regarded as the protector of sailors, children, merchants, pawnbrokers, and students, particularly in Greece, Russia, and eastern Europe. 

Facial reconstruction
In the 1950s, the bones were removed while the crypt was spruced up. While they were out, the Vatican asked an anatomy professor at the University of Bari to take thousands of minutely detailed measurements and x-rays of the relics. Flash forward to the present day, and another University of Bari expert, forensic pathologist Francesco Introna, decided to commission an expert facial anthropologist, Caroline Wilkinson of the University of Manchester in England, to reconstruct the saint's face and head using the new technology and the earlier measurements.

* There have been some questions raised about the authorship of this poem - this article sums up the controversy.

** N.B. Thus, his re-branding in the European tradition as Santa Claus, a derivation of his name in Dutch: Sinterklaas

*** The three-ball symbol of the pawn shop is said to derive from these three bags of gold. 

Here's a brief biography/documentary:

It's that time again - awkward Christmas photos

There are approximately a billion of these available; I had a really hard time choosing the most awkward and eventually ran out of time/energy to search for them. And if you know someone who likes these so much that you want a related Christmas present, there's also a book full of them called, appropriately enough, Awkward Family Holiday Photos, and a day-to-day calendar version which provides you with, presumably, 365 awkward pictures..

Feel free to link to more in the comments.  

I went looking for a shirt similar to the one above but didn't find it. Amazon has a whole bunch of aprons in a similar vein, though, for women and men:

Friday, December 2, 2016

Friday links

This is (almost) a public service announcement: if you get a free 30 day trial of Amazon Prime, you can use the unlimited 2 day shipping (plus streaming of TV shows, movies, and music) all though the holidays, and cancel afterward if you don't want to continue!

December 2, 1823: the Monroe Doctrine, the announcement forbidding countries outside of North and South American to interfere in American affairs.

Want your hoo-ha steam-cleaned but don't have a spa nearby? Here are the do-it-yourself instructions.

ICYMI, Wednesday's links are here, and include Winston Churchill's birthday, the effectiveness of polygraph tests, the obscure British comedy sketch that's the most-repeated TV program, and the Museum of Bad Art.

Thursday, December 1, 2016

December 2, 1823: the Monroe Doctrine

The occasion has been judged proper for asserting, as a principle in which the rights and interests of the United States are involved, that the American continents, by the free and independent condition which they have assumed and maintained, are henceforth not to be considered subjects for future colonization by any European powers. 

~ President James Monroe (1758-1831) (7th State of the Union address, 2 December 1823 - the "Monroe Doctrine" (wiki)) 

President James Monroe
We owe it, therefore, to candor and to the amicable relations existing between the United States and those powers to declare that we should consider any attempt on their part to extend their system to any portion of this hemisphere as dangerous to our peace and safety. With the existing colonies or dependencies of any European power we have not interfered and shall not interfere. But with the Governments who have declared their independence and maintained it, and whose independence we have, on great consideration and on just principles, acknowledged, we could not view any interposition for the purpose of oppressing them, or controlling in any other manner their destiny, by any European power in any other light than as the manifestation of an unfriendly disposition toward the United States.

~ Ibid. (a more formal statement of the Doctrine)

The Monroe Doctrine means what it has meant since President Monroe and John Quincy Adams enunciated it, and that is that we would oppose a foreign power extending its power to the Western Hemisphere, and that is why we oppose what is happening in Cuba today. That is why we have cut off our trade. This is why we worked in the OAS and in other ways to isolate the Communist menace in Cuba. This is why we continue to give a good deal of our effort and attention to it. 

~ President John F. Kennedy (wiki) (1917-1963) (news conference, 29 August 1962)*

There is one safeguard known generally to the wise, which is an advantage and security to all, but especially to democracies as against despots. What is it? Distrust. 

~ Demosthenes (wiki) (ca. 384-322 B.C.) (Second Philippic, sec. 24)

John Quincy Adams,
 author of the Monroe Doctrine
Today is the anniversary of the proclamation of the "Monroe Doctrine" (wiki) in the Seventh State of the Union address of U.S. President James Monroe (wiki) (served 1817-1825) in 1823. Formulated largely my Monroe's secretary of state, John Quincy Adams  (wiki) (1767-1848),** the Doctrine stated that the American continents were no longer open to European colonization and that the United States would view with displeasure any further European intervention in the Americas.

The Monroe Doctrine consisted of four main points:

1. The United States would remain neutral in European affairs and not get involved in European conflicts.

2. The United States would not interfere with current European colonies in the Western Hemisphere.

3. No European nation would be allowed to establish a new colony in the Western Hemisphere.

4. If a European nation would try to interfere with a nation in the Western Hemisphere, the United States would view that as a hostile act and respond accordingly.

Although never formally recognized in international law, the Doctrine has been successfully invoked regularly times and became a key principle of American foreign policy.*** As imperialistic tendencies grew, however, the Monroe Doctrine was viewed with suspicion by Latin-American countries, who associated it with the possible extension of U.S. hegemony - and it has been used a half-dozen times to justify U.S. intervention in Latin American affairs. 

* N.B. The Cuban Missile Crisis (wiki) followed about a month and a half later.

** Adams succeeded Monroe as the 6th President of the United States in 1825.

*** Perhaps the most flagrant "violation" of the Monroe Doctrine took place in 1862, when France invaded Mexico and installed a puppet government under the emperor Maximilian. President Lincoln was powerless to intervene because of the ongoing U.S. Civil War. Maximilian was deposed and executed in 1867.

Here's a brief video explanation:

The above is based on Ed's Quotation of the Day, only available via email. If you'd like to be added to his distribution list, leave your email address in the comments.