This is when the next leap year falls and why we have them

As the end of February approaches, many are wondering when the next leap year is and how often they occur.

Leap years tend to take place every four years, leading many to search for answers to a host of questions about them, and their origins.

This year - 2021 - is not a leap year, meaning there are 365 days in the annual calendar this time around, but the next one isn't far off.

When was the last one, when is the next one, and why do we have them at all? Read on to discover all there is to know about leap years.

What is a leap year?

A leap year is a year in which an extra day - 29 February - is added to our annual calendars.

The 29 February is known as Leap Day and anyone born on this day is generally referred to as a Leapling.

Leap years occur every four years.

Why do we have a leap year?

Broadly speaking, leap years happen every four years to keep our calendars in sync with the seasons.

There are 365 days in the Gregorian calendar - used in most parts of the world, including the UK - but it takes the Earth a little longer to complete a full orbit of the Sun.

A full orbit of the Sun takes 365.25 days so an extra day is added to the calendar every four years to correctly align the solar year with the astronomical seasons.

If the day was not added then the calendar would be out of sync by five hours, 48 minutes and 45 seconds each year, which could have a big impact over time.