Ambitexto

Britain once went to bed on 2 September and woke on the 14th.

• A year lasts about 365 days and six hours, so every fourth year gets 29 February.
• Caesar's rule ran eleven minutes a year too long: by 1582, spring had slipped ten days.
• The Treasury refused to lose eleven days of tax, so the tax year still starts on 6 April.

29 February is not a quirk. It is a repair two thousand years old, and it still works.

Words for the text

calendar

A list of all the days, weeks and months of the year.

leap year

A year with 366 days. It has a 29 February.

season

Spring, summer, autumn or winter.

equinox

A day in spring or autumn when day and night are the same length.

century

A hundred years.

The opening of the text

A year is not 365 days

On the night of 2 September 1752, everybody in Britain went to sleep. The next morning was 14 September. Eleven days were gone, and the reason for it is also the reason for 29 February.

Most years have 365 days. But once every four years, February gets an extra day, the 29th, and the year has 366. We call it a leap year. Why do we need it? The answer is not on Earth. It is in the sky.