More or Less - The messy history behind the modern calendar

The messy history behind the modern calendar

Download The messy history behind the modern calendar

This year, the UK has had its hottest May and June days on record, with the mercury hitting the high thirties.

But while the markings on a thermometer seem scientific and regular, the way we split up our calendar does not. Why, for instance, does May have 31 days and June have 30?

To find out why our calendar has its modern form, we speak to Kristen Lippincott, former director of the Royal Observatory at Greenwich, and author of The Story of Time.

If you have seen a number in the news you think we should take a look at, email moreorless@bbc.co.uk

Presenter: Tim Harford
Producer: Josh McMinn
Series Producer: Tom Colls
Programme Coordinator: Brenda Brown
Sound Engineer: Giles Aspen
Editor: Richard Vadon

Published on Sunday, 27th July 2025.

Available Podcasts from More or Less

Subscribe to More or Less

We are not the BBC, we only list available podcasts. To find out more about the programme including episodes available on BBC iPlayer, go to the More or Less webpage.