The Bully Mnemonic & Calendar Variations

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Bully Mnemonic Topics:

• The Bully Mnemonic
• The Bully Mnemonic & Calendar Variations

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The Bully Mnemonic reminds us that there are approximately 31556928 seconds in a tropical year:

$$1TropicalYear\approx (10330-0.40)\times 3055sec=31556928sec$$

Knowing the number of seconds in a tropical year can help one understand the structure of various calendars, which typically are attempting to approximate the tropical year as a multi-year average.

Julian Years & Gregorian Years

Initial Calculations

There are 86400 seconds in a day:

$$1Day=24hours\times \frac{60min}{1hour}\times \frac{60sec}{1min}=86400sec$$

The number of seconds in 365 days is:

$$365Day=365\times 86400seconds=31536000seconds$$

which is 24.222% of a day less than a full tropical year:

$$\frac{31536000-31556928}{86400}=365\times 86400seconds=31536000seconds$$

The number of seconds in 366 days is:

$$366Day=366\times 86400seconds=31622400seconds$$