3Qs: ‘Leaping’ into the realm of science

Today is Feb. 29, the extra day we add to the cal­endar in leap years. But why do we need this extra day, and what is the sci­ence behind it? And what about the lesser-​​known leap second – which del­e­gates from more than 70 nations recently debated whether to abolish? We asked Murray Gibson, dean of the Col­lege of Sci­ence, to answer these ques­tions – as well as how early sci­en­tists dis­cov­ered the need to adjust the calendar.