Today is Leap Year's Day, a once-every-four-year event and all to do with the rotation of the earth, the Gregorian calendar and all stuff planetary, so here follows a brief scientific description as to why it happens:
The rotation of the earth actually lasts about 365.2422 days (called a 'Solar Year' or a 'Tropical Year') so leap years are needed to keep our calendar in alignment with the earth's revolutions around the sun. After 100 years, a 365 days a year calendar would be more than 24 days ahead of the season. The extra day comes (nearly) every four years on February 29th and is added to correct the actual number of days in a year. This year it falls on a Friday, an occurrence that happens once every 28 years (it last happened in 1980) and will occur again in 2036.
In the Gregorian calendar, our calendar, the following three criteria determine which years will be leap years:
1. Every year that is divisible by four is a leap year;
2. of those years, if it can be divided by 100, it is NOT a leap year, unless
3. the year is divisible by 400. Then it is a leap year.
According to the above criteria, that means that years 1800, 1900, 2100, 2200, 2300 and 2500 are NOT leap years, while year 2000 and 2400 are leap years.
Not being a scientist or a mathematician, I am merely intrigued by the patterns. Pondering planets, moons, stars, the sun, patterns and outerspace reminded me of crop circles. These perfectly formed, mathematically rational patterns are, without doubt, beautiful. Their beauty entirely due to the perfection of the maths and the perfection of the execution. The idea that they are created by teams of humans, rather than alien spaceships overnight, is, of course, entirely feasible and fully justified by maths and logic.Then again, perhaps they are some kind of once-in-an-astronomical-universal-cycle kind of phenomenom!
