July 22, 2012 - Casual Pi Day

Pi is the relationship of a circle's circumference to its diameter. No matter how large or small a circle is, the proportion of the distance around the circle to the distance across its widest part is EXACTLY the same!

That exact number starts off 3.14159265...and goes on for bajillions of non-repeating digits. Because pi starts with 3.14, we celebrate Pi Day on 3/14, or March 14^th.

But today is not that date. Why are we celebrating Casual Pi Day today?

Well, the other name for the day gives us a hint—it's Pi Approximation Day.

It's hard to be exact about pi when the decimal digits go on forever (and don't even repeat). So we have to use approximate numbers when we actually use pi, and a really approximate way of expressing the approximation is the fraction 22/7. And that's why today, the 22^nd day of the 7^th month, is Pi Approximation Day!

Use a calculator to see what 22 divided by 7 is. How many decimal places match pi?

By the way, you can get a picture of pi being all casual and summery on a T-shirt or mug here. 

Approximate, ashmoximate!

When we are doing mental math or solving real-life problems in our heads, we often don't need the exact answer. Instead, we can use just an approximation of the right answer. And we do this by estimating—rounding off and THEN adding or multiplying or whatever we are trying to do...

Practice your estimation skills with these PBS games or these Gamequarium games. 

Also on this date:

Revolution Day in the Gambia 

National Tree Planting Day in the Central African Republic 

Birthday of the king of Swaziland 

Anniversary of three first-flights-around-the-world 

July 21, 2012 - Woodie Wagon Day

Back in the 1940s, steel was being salvaged for the war (WWII) effort, and so car manufacturers used wood as a replacement. Of course, the engine and axles HAD to be made of steel, but cars were built with wooden passenger compartments, or sometimes just wood panels along their sides. This style was seen in many sedans and family station wagons during the 1940s and 1950s, but then its popularity began to drop. When popularity drops, the price drops—but when Woodie Wagons became cheap, they had a revival in popularity. This time, it was young people, especially surfers who needed a looong car to hold their boards, who were buying used woodies.

Woodie Wagons are now a bit of a legend! But making cars with actual wood is long gone—the last was made in 1971. Newer woodies are made of steel with simulated wood grain and dimensional faux-frameworks. Safety regulations make cars made with wooden passenger compartments an impossibility!

But woodies live on in song lyrics, on T-shirts and key-chain fobs, and in new and used cars--and they're still popular enough, in a really retro way, to get their own "holiday"!

Also on this date:

Independence Day in Belgium 

Victor Schoelcher Day in Martinique 

July 20, 2012 - “Peace and Freedom” Day in North Cyprus

Once upon a time, a fair island in the lovely waters of the Mediterranean Sea was home to both Greek and Turkish people. The two groups had different languages and religions, but they lived and worked side-by-side peacefully for many years.

And then the British took over the island, Cyprus, and began to pit the groups against each other (according to some), and also teachings in schools and churches and mosques began to emphasize separation and nationalism. Struggles and fights began to break out between the two groups, and both sides have done senseless, violent acts. From the first killing in 1955, the two ethnic communities began to pull more and more apart.

When a Greek nationalist group staged a military coup and threw out the Cypriot president, in July of 1974, people were killed and jailed, and Turkish people were rightly upset by the horrible behavior of the Greek group....

...and then violence was used to “stop” violence. On this date in 1974, Turkey invaded Cyprus in what was called (by Turks) “the 1974 Peace Operation.” This operation was supposed to safeguard the republic but ended up dividing the country.

My daughter has been to Cyprus and said that it was so odd to be in cute little tourist shops in the capital city of Nicosia and then to suddenly come upon the “buffer zone,” sometimes called the Green Line: a barbed-wire fence with warning signs, abandoned houses and cars and streets, and armed soldiers on patrol.

She said that people unlucky enough to have lived in the area now inside the buffer zone lost everything that they hadn't grabbed in their hasty fleeing of the violence during that long-ago July. I'm sure they didn't imagine having their stuff still sitting there, inaccessible to them, almost 40 years later!!!

As North Cypriots get out their Turkish and North Cyprus flags and gather to watch military parades today, ready to celebrate Peace and Freedom, we would be wise to consider that these people had more of both before any of this violence started, when the two ethnic groups lived side by side as “just” Cypriots. When voices on the radio and talking heads on TV, and people on Facebook and even friends and relatives try to stir up fear and hatred of other ethnic groups, even if they are saying that they are just looking out for your safety and economic best interests, try hard to hold onto a more tolerant and neighborly perspective!

Also on this date:

Moon Day (here and here)

July 19, 2012 - The Metro Opens in Paris

– 1900

The underground trains of Paris—in other words, the subway—opened for the first time on this date in 1900.

The first line that opened provided transport to the 1900 summer Olympic Games at the Bois de Vincennes. Parisians immediately loved the Metro—and thirty thousand tickets were sold on the first day alone!

That first year, 17 million passengers used the Metro—even though the subway “system” consisted of only one line. 

Nowadays, there are fourteen lines, and more than four million passengers ride the trains EVERY DAY! That comes up to a grand total of more than 1.47 BILLION per year! That makes the Paris Metro the second busiest subway system in Europe. 

(Want to guess the #1 busiest in Europe? How about the busiest in the world? Answers at the bottom of the post.)

One of the system's stations, Chatelet-Les Halles, which has five Metro lines and three RER commuter rail lines, is the world's largest Metro station.

The Metro is known for its Art Nouveau entrances.

How do you build train tracks BELOW a city?

Most of the underground lines were laid under already-existing streets. The soil of Paris is not conducive to deep digging, so most of the lines are not that far below the surface, and they were created with what is called the “cut-and-cover” method. This involved digging a deep trench along a main street. (In order to keep traffic to a minimum, this was often done one small section at a time.) The trench was lined with brick or concrete, and then given a roof of strong steel girders. Then the trench section was covered with road, sidewalk, or whatever..and the construction area was moved down to the end of the section just built. This cut-and-cover method of tunnel building is quite inexpensive and therefore often used today.

There are exceptions to the shallow-tunnel generalization, including tunnels that go underneath Paris's river, the Seine. Metallic caissons from 20 to 40 meters long were assembled on the bank of the river and then gradually driven into the river bed, apparently providing an interesting spectacle for passersby. (A caisson is a large watertight chamber that is open at the bottom, used during construction work done under water. The water is kept out by air pressure.) In order bore the tunnel, the ground was frozen (extra-super-duper frozen, at minus 24 degrees Celsius!) using calcium chloride brine.

To learn how some subway tunnels are built these days, check out the Washington Post's infographic. 

ANSWERS to questions above: The busiest subway system in Europe is Moscow, Russia, and the busiest in the world is in Tokyo, Japan. Paris's Metro is only #8 in the world, behind: Toyko, Japan; Seoul, South Korea; Moscow; Beijing, China; Shanghai, China; Guangzhou, China; New York City, U.S.

Also on this date:

Arts and Artists Day 

Anniversary of the first parking meters. 

July 18, 2012 - Baseball Fans Get a Perfect Game

—1999

Baseball has always seemed just a little too slow and boring to watch, I've always thought. And a perfect game must just start out sooooooooo boring.

Because in that game, one team would just never get on base. No hits, no runs. No walks. No errors (at least, none that result with a player getting on base!) A shut-out. A no-hitter.

But then..through all the haze of boredom—hey, nothing's happening here—the audience would start to realize: hey, so far, it's a perfect game!

And that doesn't happen very often. So all of a sudden a boring game would become an exciting game.

And I imagine that's what happened in Yankee Stadium when David Cone was pitching for the New York Yankees on this date in 1999. I imagine the home crowd beginning to whisper that the game had been perfect for Cone, so far—whispering because they would not want to jinx it. (Of course, I'm playing here—there's no such thing as magically jinxing something!) The fans would all be wondering if a Montreal Expo player would get a hit and spoil Cone's perfect game. Would one of the Yankee fielders not get to a fly ball, or maybe make an error? Would Cone himself let down, somehow, and walk somebody?

There was a rain delay. I can just imagine people thinking, once we're back from this rain delay, the perfect game is going to go right down the tubes!

But Expo player after Expo player took the plate and was out – out – out. Cone kept up the pitching, and the Yankees backed him up with excellent fielding. One time the right fielder had to make a diving catch to keep the perfect game going. Another time an Expo hit a ball hard between first and second base. The second baseman shot an expert throw to make the out and save the game.

In the meantime, the Yankees scored five runs! There was a walk and a batter who got on because he was hit by a pitch; Yankees made singles and doubles and two home runs! (Hmm...I guess this was NEVER a boring game. My apologies to baseball fans everywhere!)

That last inning would have been very exciting! Everyone knew by now what was on the line. So far in more than a century of Major League Baseball history, there had only been 15 perfect games. The 42,000 fans must have been holding their collective breath while watching Cone pitch to what they hoped would be the last three batters. The first batter was up—and Cone struck him out. Then the second batter hit a big, soft, easy-to-catch fly ball into left field. But...it wasn't so easy to catch, because the summer afternoon sun was exactly where the ball was. Left fielder Ricky Ledee was blinded and struggled to find the ball in the sky, but he somehow made the catch! And then the last batter popped up a foul ball—and the third baseman caught it, too!

David Cone had pitched the 16^th perfect game in all of baseball history, and he fell on his knees, right into the arms of his catcher!

Also on this date:

Extreme Vehicle Day 

Activist and statesman Nelson Mandela's birthday 

July 17, 2012 - Wrong Way Corrigan Day

What a weird name for a holiday! I had no idea what this was about and had to look it up. It turns out that a guy named Douglas Corrigan got a pretty special nickname: Wrong Way Corrigan. Here's his story:

On this date in 1938, Corrigan got into his 1929 Curtiss Robin monoplane in an airfield in Brooklyn, New York. He'd let people know his flight plan; he was going to fly westward to Los Angeles, California. But when he took he, he swung the plane eastward and headed out over the Atlantic Ocean. About 3,000 miles later—more than 28 hours later!—Corrigan landed in Dublin, Ireland. He had made the nonstop solo flight without radio or special navigation equipment—totally against American and Irish flight regulations. He said he made the mistake because he'd accidentally followed the wrong end of his compass needle, but I would think that he would have noticed he was flying over an ocean rather than land!

Still, Corrigan got a hero's welcome for his feat, and the nickname!

And now he has a day named after him. Does that mean that a really big mistake is a stroke of genius?

(No. No, it does not. At least, not very often, it doesn't!)

Also on this date:

Anniversary of an ancient solar eclipse 

Disneyland's birthday 

July 16, 2012 - Global Hug Your Kids Day

A woman named Michelle Nichols started this holiday after suddenly losing her eight-year-old son to brain cancer. She is excited that people all over the U.S. and, recently, world, are aware of her goal—that every kid get a hug from a parent or other caregiver.

And it's not just about today. Nichols is hoping that parents and caregivers will hug their kids EVERY day.

Some people say, hey, it's not just about kids. Let's all hug each other—parents, grandparents, aunts and uncles and cousins, sisters and brothers, friends!

I say, it's not just about hugs. We can try to extend kindness and love to our friends and family every day, in all sorts of ways.

You can check out Nichols's Hug Your Kids website here. 

Celebrate!

Obviously, you can celebrate the day by hugging your friends and loved ones. But you can also send a hug (or two) through the mail, join author Jez Alborough's Hug Club, or make a soda hug. 

Also on this date:

World Snake Day 

Medical researcher Joseph Goldberger's birthday