NIZAMABAD: Why does February have 29 days every four years? How did calendar reforms shape what we follow today? For many people, these questions can be tricky. For the past several years, however, 78-year-old retired teacher Dasari Vijayanand Rao has been working to ensure they have clear answers.
Vijayanand, a former school headmaster, has been conducting awareness programmes on the concept of leap years, focusing on teachers, students and youngsters. By the end of 2025, he had addressed nearly 200 such sessions. During his service, he taught Science and Mathematics. While taking part in awareness programmes at schools, he encourages students to come up to him with their doubts in school work also.
Recently, the Sneha Society for Rural Reconstruction organised one such programme, attended by students and other participants. Explaining the concept, Vijayanand says a calendar year has 365 days, while a solar year — the time taken by the Earth to complete one orbit around the Sun — is about 365 days, 5 hours, 48 minutes and 46 seconds.
To account for this, Julius Caesar, on the advice of astronomers in 46 BCE, rounded it to 0.25 days and introduced an extra day every four years, creating February 29 as ‘Leap Day’, effective from January 1, 45 BCE. However, this rounding added an excess of 11 minutes and 14 seconds each year.
Over 400 years, this led to 3.12 extra days, causing seasonal shifts. To correct this, Pope Gregory XIII introduced the Gregorian calendar in 1582. Under this, a leap year occurs every four years, except century years, which must be divisible by 400 to qualify. This removes three leap years every 400 years.
As part of the reform, 10 days between October 5 and October 14, 1582, were skipped to realign the calendar. Vijayanand explains that by the year 3200, a slight discrepancy of nearly one day emerges again, meaning 3200 and its multiples (up to 76,800) are not leap years, while 80,000 and its multiples are.
Speaking to TNIE, SNESOR secretary S Suddaiah says similar programmes would be organised in rural areas as well.