Topic
Clocks
3 articles
Astronomy
Why isn’t the earliest sunset on the shortest day?
The shortest day of the year ought to have the earliest sunset and the latest sunrise. Check a timetable and neither of them lands there. The sunsets start getting later a fortnight before the days start getting longer.
History of science
Why are there 60 minutes in an hour?
Everything else we count goes in tens. Time stubbornly does not, and the reason is a choice made five thousand years ago by people who had no easy way of writing a third.
Biology
How does a young sunflower follow the sun?
A sunflower has no muscles and nothing inside it that moves. A young one still swings its head halfway across the sky each day — and swings back overnight, in the dark.