16 MAY / JUNE 2022 popularmechanics.co.za
HOW YOUR WORLD WORKS
PHYSICS
/ BY CAROLINE DELBERT & DAISY HERNANDEZ /The case for the
59-second minute
and why it could
wreck us
A
DAY IS 86 400 SECONDS LONG, EXCEPT
that it never really quite is, not exactly. That
number is an excellent average, but the
Earth’s rate of rotation is in constant flux.
After 2020 clocked some of the fastest
days on record since 1960, scientists are
considering subtracting a second from an
upcoming calendar with a 59-second minute, or negative
leap second, to align our UTC (the Coordinated Universal
Time, used to set clocks around the world) with the time
set by the rotation of the Earth (UT1).
In 1971, the International Telecommunications Union
(ITU) set a standard that the UTC would never be more
than 0.9 seconds ahead or behind UT1, says Demetrios
Matsakis, chief scientist at Masterclock, a precision timing