Answer:
The Leap Year is related to Astronomy, since its reasoning is directly tied to the Earth's translation movement around the Sun, which occurs after around 365.2425 days, or 365 days, 5 hours, 48 minutes and 45.2 seconds. In the Gregorian calendar, used by most countries, one year is made of 365 days. So, each year, about 6 hours are left behind. To correct for this, every four years, one day is added to the calendar, making it a Leap Year. But this is a slight over correction, so every 100 years, the Leap Year is skipped, like in 2100, and every 400 years this skipping is not made, like in 2000.