Tahun Kabisat (Leap Year)
When Is the Next Leap Day?
Leap days are needed to keep our calendar in alignment with the Earth's revolutions around the Sun.
It takes the Earth approximately 365.242189 days – or 365 days, 5 hours, 48 minutes, and 45 seconds – to circle once around the Sun. This called a tropical year.
Without an extra – or intercalary – day on February 29 nearly every four years, we would lose almost six hours every year. After only 100 years, our calendar would be off by approximately 24 days in relation to fixed seasonal days days like the vernal equinox or winter solstice.
Caesar Introduced Leap Years
Roman general Julius Caesar implemented the first leap day in his Julian Calendar, which he introduced in 45 BCE (Before Common Era). A leap day was added every four years. At the time, leap day was February 24, and February was the last month of the year.
Too Many Leap Years
However, adding a leap day every four years was too often and eventually, in 1582, Pope Gregory XIII introduced the Gregorian Calendar. This calendar, which we still use today, has a more precise formula for calculation of leap years, also known as bissextile years.
USA 1752: Why Are Some Days Missing?
Traditions & Folklore
Leap day as a concept has existed for more than 2000 years, and is still associated with age-old customs, folklore and superstition. One of the most well-known traditions is that women propose to their boyfriends, instead of the other way around.
What's a Leap Second?
Leap Months
The ancient Roman Calendar added an extra month every few years to maintain the correct seasonal changes, similar to the Chinese leap month.
Different Types of Calendars
- The Gregorian Calendar – used in most countries today
- The Julian Calendar
- The Mayan Calendar
- The Chinese Calendar
- The Roman Calendar
Tahun kabisat (bahasa Inggris: Leap year) adalah tahun yang mengalami penambahan satu hari dengan tujuan untuk menyesuaikan penanggalan dengan tahun astronomi.[1]
Dalam satu tahun tidak secara persis terdiri dari 365 hari, tetapi 365 hari 5 jam 48 menit 45,1814 detik. Jika hal ini tidak dihiraukan, maka setiap 4 tahun akan kekurangan hampir1 hari (tepatnya 23 jam 15 menit 0,7256 detik).
Maka untuk mengkompensasi hal ini, setiap 4 tahun sekali (tahun yang bisa dibagi 4), diberi 1 hari ekstra: 29 Februari. Tetapi karena 5 jam 48 menit 45,1814 detik kurang dari 6jam, maka tahun-tahun yang bisa dibagi 100 (seperti tahun 1900), bukan tahun kabisat, kecuali bisa dibagi dengan 400 (seperti tahun 2000).
