Ready for a Night In? Join Tabby and Kate as they talk about calendars and how they have played a significant role in our progression as a civilization. 

00:45 Why does leap day exist? It's complicated 

01:35 Calendar Intercalation: a day, week, or month added to a calendar to realign the lunar calendar with the solar calendar 

01:55 Lunar Calendars start as civilizations first prehistoric calendar 

02:45 Intercalations in the lunisolar calendar exist as months. This is necessary because the lunar calendar is 354 days long but a solar year is approx. 365 days long, so every few years a month was added to the lunisolar calendar to make up for the lost days that come from a lunar calendar 

04:23 Calendar science leads to societies having many calendars 

04:35 The Metonic Cycle was a 19-year cycle that included an intercalary month 7 times in a 19 year cycle to keep the average length of the year in 19 years approx. 265 days long 

06:30 Mayan calendar 

09:00 The Persian Calendar in the 11th century predicts the tropical year extremely accurately 

09:41 The Gregorian calendar and why it replaced the Julian Calendar 

13:30 Other cultures still maintain their lunisolar calendars for cultural traditions 

16:55 The two types of lunar calendars 

18:00 Bachelor’s Day 

Thanks again for listening as always! Be sure to follow our social media! @Tylerandfrantz

Intro Song by: Joakim Karud youtube.com/joakimkarud

Additional music provided by the YouTube Audio Library