Sunday, January 08, 2006

Just a "Leap Second"

I feel like I've been "slowing down" a bit lately. It could be my "advance age" or all the new homes I've been selling. Or it could be that the World is "moving alittle slower" this last year. Our Earth's Official Timekeepers have just added a "leap second" to the calendar at midnight on Dec. 31st. Maybe that's it. I detected it, didn't you?

This was the first leap second to be added in seven years - though they've added 22 of them between 1972 and 1999. Every four years our calendars add its "quadrennial cousin" the "Leap Day", Feb. 29th on "Leap Year". "Thirty days has September, April, June and November. All the rest have 31 except February (28)...which in four, adds one more, making 29."(sic) This has been keeping the Earth's clock in sync with "atomic time" since 1972, when the timekeepers first started using Coordinated Universal Time (UTC). This is the legal standard in most places. UTC ticks off time in "atomic seconds" - each of which is equal to the time needed for a cesium -133 atom to perform 9,192,631,770 complete oscillations. It is built to stay in step with Greenwich Mean Time, in which the length of seconds varies slightly, depending on how long the Earth actually take to rotate. In recent years, Earth spun a bit faster than it had been spinning - hence the lack of leap seconds. But experts say that was exceptional. Over the long haul, Earth's rotation is gradually slowing down. In just a few decades, we may need to add a "leap second" every year. In just a few centuries, we may need to add one every month. You and I probably won't care by then will we?

Back in 1851 on this date (1/8) Jean Foucault, a scientist demonstrated definitively that the Earth rotated on its axis with the "Foucault Pendulum". I don't think he was that concerned about seconds. I remember taking my classes on a "field trip" to the Griffith Observatory. There they had this wondrously gigantic pendulum in the center atrium that demonstrated the "Earth's motion" ala Foucault. It was a giant ball on a wire connected to the dome. It swung, knocking over little pegs around a circle in the indented floor and "never" stopped swinging. Fascinating! Each peg was probably an hour.

Also on this date in 1942, Stephen Hawking, an English physicist and mathematician was born. He has also added to our understanding(?) of time with his "Brief and Briefer History of Time" (not mine.) Coincedentally, Galileo Galilei, an Italian astronomer, died on this date in 1642 Three hundred years to the day! He, of course, had a difference of opinion with the Catholic Church at the time about "rotation" ie. "time" and spent most of his declining years under "house arrest" because he dared to think the Earth rotated around the Sun. His first inkling that this might be true, was from observing the slight swinging motion of the chandeliers in "church" as he prayed for his soul. He was later motivated to build a stronger telescope and detected "moons" that "rotated" around a different planet, not the Earth, and not the Sun. Shocking! When we toured the Vatican Hallways leading to the Sistine Chapel, our guide pointed out the gigantic picture of Pope Urbanus(?) who "excommuicated" Galileo, could've had him put to death, and kept him "arrested". I asked the guide if he was Galileo's Pope. She said yes. We then went with our singing group, Mountainside Master Chorale, one of many that day, and sang in the Sistine. What a thrill!

During my years of teaching, 38 or so, I usually "declared" "Leap Day" in my class on the years divisible by 4, Feb. 29th and we tried to think up all kinds of creative things to do. We didn't just have the girls running everything...(class monitors etc.) We tried to have special events, publications, poems, activities that were fun and involving. I think we even tried to invent a "dance" for "Leap Day". Sometimes, the quadrennially celebrated Olympics, was one of our "events". I'd make sure and teach Summer School that year and have a wonderful theme with the Olympic Events for kids, and the the historical study of Greek Democracy/History, Greek Myths, drama. I once came dressed as "Socrates" in a long, flowing white toga and I did nothing all day but "ask questions" and "answer questions by asking questions"...the Socratic Method of learning. What fun and very frustrating to my students. Teaching, for me, was a "Performing Art". Here's hoping there are many more "leap seconds" for many more "leap years" of learning. Bob

2 Comments:

At 5:12 PM, Blogger BOB! Your Life Preserver said...

"Advanced Age"...see I can't even write it. Bob

 
At 3:17 PM, Blogger BOB! Your Life Preserver said...

All Right! My Blog is now a "Link" on my High School Class of '57's 50th Reunion Website. If I only knew how to link to it from here? Bob

 

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