Usually I don't do this, but I think it will be quite interesting. To give some scientific facts on this historical day.
February 29th comes only once every four years, known as leap year. It is to compensate the extra quarter of a day in every year.
Long time ago, there was this guy named Julius Caesar (not to be confused with Inter Milan's goalkeeper) who introduced the Julian Calendar. He knows that the Earth revolves around the Sun every 365 rotations on its axis (known as days), but there was a little bit more. About a quarter of a day more. So every four years, a day will be added to February, the shortest month of the year (God knows why). Every year that is divisible by four is called a leap year.
But there was an error. A year wasn't exactly 365.25 days. It was slightly less. I don't know how they identified the error, but Gregory corrected it. Nope, he did not actually. Gregorian calendar, the current solar calendar widely used throughout the world today, got its name from Pope Gregory XIII who decreed the proposal submitted by Aloysius Lillius. Where do I know all these? Thank Wikipedia.
It seems that a full year is neither 365 days nor 365.25 days. It was slightly shorter. 365.2425 days, or 365 days, 5 hours, 29 minutes and 12 seconds to be exact. So what did that Lillius fella did to correct the erroneous Julian calendar? The leap year rule was redefined as, "Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100; the centurial years that are exactly divisible by 400 are still leap years." For example, the year 1900 was not a leap year; the year 2000 was a leap year.
How about calculating the day? The day is currently defined as 24 hours, an hour is 60 minutes and a minute is 60 seconds, hence a day should have 86400 seconds. However, the SI unit for a second is not defined as 1/86400th of a day, but rather as the duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom (again, Wikipedia). Using this definition, the Earth is currently revolving around its axis once every 86400.002 seconds. Therefore, a second needs to be added to civil clocks every now and then to synchronize the current time with the Earth's movement. This extra second is called a leap second (I never know about this leap second thingy) and is usually added on June 30th or December 31st.
What effect does this additional day has on our lives? Well, one thing, babies born on this day will have the unfortunate fate of celebrating most of their birthdays on either 28th of February or 1st of March. They might even be ridiculed by their friends for not having a birthday this year (not this year, but some other years), thus not having a party or presents. Pranksters (well, not really a high-class prank) might also say they'll treat you to a free lunch or dinner on 29th of February on non-leap years.
Well, for me, it means an additional day of wait for my scholarship. Good thing PETRONAS never pays their scholars exactly on 1st of every month. I already got my pay actually, but I just want to mention it. Heh.
Wait. It still means I have to wait for an additional day for my next scholarship. Uhh.
And I had a test just now. On the 29th of February.
February 29th comes only once every four years, known as leap year. It is to compensate the extra quarter of a day in every year.
Long time ago, there was this guy named Julius Caesar (not to be confused with Inter Milan's goalkeeper) who introduced the Julian Calendar. He knows that the Earth revolves around the Sun every 365 rotations on its axis (known as days), but there was a little bit more. About a quarter of a day more. So every four years, a day will be added to February, the shortest month of the year (God knows why). Every year that is divisible by four is called a leap year.
But there was an error. A year wasn't exactly 365.25 days. It was slightly less. I don't know how they identified the error, but Gregory corrected it. Nope, he did not actually. Gregorian calendar, the current solar calendar widely used throughout the world today, got its name from Pope Gregory XIII who decreed the proposal submitted by Aloysius Lillius. Where do I know all these? Thank Wikipedia.
It seems that a full year is neither 365 days nor 365.25 days. It was slightly shorter. 365.2425 days, or 365 days, 5 hours, 29 minutes and 12 seconds to be exact. So what did that Lillius fella did to correct the erroneous Julian calendar? The leap year rule was redefined as, "Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100; the centurial years that are exactly divisible by 400 are still leap years." For example, the year 1900 was not a leap year; the year 2000 was a leap year.
How about calculating the day? The day is currently defined as 24 hours, an hour is 60 minutes and a minute is 60 seconds, hence a day should have 86400 seconds. However, the SI unit for a second is not defined as 1/86400th of a day, but rather as the duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom (again, Wikipedia). Using this definition, the Earth is currently revolving around its axis once every 86400.002 seconds. Therefore, a second needs to be added to civil clocks every now and then to synchronize the current time with the Earth's movement. This extra second is called a leap second (I never know about this leap second thingy) and is usually added on June 30th or December 31st.
What effect does this additional day has on our lives? Well, one thing, babies born on this day will have the unfortunate fate of celebrating most of their birthdays on either 28th of February or 1st of March. They might even be ridiculed by their friends for not having a birthday this year (not this year, but some other years), thus not having a party or presents. Pranksters (well, not really a high-class prank) might also say they'll treat you to a free lunch or dinner on 29th of February on non-leap years.
Well, for me, it means an additional day of wait for my scholarship. Good thing PETRONAS never pays their scholars exactly on 1st of every month. I already got my pay actually, but I just want to mention it. Heh.
Wait. It still means I have to wait for an additional day for my next scholarship. Uhh.
And I had a test just now. On the 29th of February.
i love this post.
ReplyDeleteHAHAHHAHAHAHA
sounds nerdy eh? :)
but really i do.
tq, tq! for posting about leap year.
i had a discussion with a friend before about it.
and u seem to clear it well.
(yes, i do gossip about leap year! hahaha)
and i think Islam calender is romantic because it follows the moon.
:)