Seasons & calendars
Where did the names of the months of the year come from? Why are there seven days in a week? And how are seasons defined? Find out all the answers and more here. Plus, find out how calendars vary among different cultures around the world.
The first day of spring in the UK astronomically occurs on the vernal equinox, 20 March 2018. But did you know there are actually three main definitions for the season coming from astronomy, meteorology and phenology?
Easter falls on a Sunday between 22 March and 25 April, but which Sunday requires an astronomical calculation.
While days and years are (fairly) neat astronomical events, what explains months, weeks, hours and minutes?
Observations of the Moon determine the timing of the Islamic year Al Hijra and its months including the holy month of Ramadan. Find out the dates here.
Why change the clocks, which way should they go, and whose idea was it in the first place? British Summer Time explained.
A year on Earth can be split into four as we complete our orbit of the Sun. Each of these are marked by an equinox or solstice.