December 31st, 2016. The clock was at 23:59:58. Tick. The clock struck 23:59:59. Tick.
Now, in a normal year, the time would change to 00:00:00, January 1st. But 2016 was no normal year: Lin Manuel Miranda’s Hamilton had become a nationwide sensation, Harambe had been transformed into a meme, Pokemon Go had taken over everyone’s social life, and the Earth was spinning too slowly. Yes, the Earth’s spin was slowing down, enough to make a noticeable difference in the length of days. Slowly, days became longer and longer and, gradually, our increasingly digital world came out of sync with the spin of the Earth.
In order to account for this inconsistency, on December 31st, 2016, the clock struck 23:59:60. Suddenly, a minute had 61 seconds. Of course, this time was immediately followed by 00:00:00 on January 1st, 2017. From then on, every minute was returned to its original duration of 60 seconds. But 2020 came with a slew of new problems, where COVID-19 took the spotlight. The daily updates on the status of the pandemic took over the news, and pushed other current events out of people’s attention. For the few passionate physics enthusiasts, 2020 had another significant event – the speeding of the earth. 2020 recorded some of the shortest days in recent memory because of the Earth’s increasing rotational speed. While this may not be affecting us yet, letting these inconsistencies occur without any adaptation would result in humanity being minutes out of sync with ‘real’ time. So what do we do? Well, the International Earth Rotation and Reference Systems Service (IERS) have been discussing a possible negative leap second on June 30th, 2021. A negative leap second, just like the name suggests, is the opposite of a leap second. Instead of having 61 seconds in a minute, this time adjustment technique would create a minute with only 59 seconds. However, nothing is set in stone yet. The time and date of these leap seconds are meticulously calculated to account for changes in the revolution of the Earth.
27 leap seconds have been created since the first leap second in 1972. Although some of you might be vaguely interested in this one second difference between the conventional minute and a leap second minute, for the less enthusiastic there are some major issues that could be a result of this time keeping technique. When the IERS decides to add a leap second, they usually give over a month’s notice. However, despite this early warning, many technological systems fail to account for this inconsistency in time. Slowly, these technologies will begin to run into bugs and errors, due to disagreements over what time it is. Although most phones, computers, smartwatches, and applications will have the IERS database directly connected to their time keeping software, it is still important to watch out for these small errors because, over time, it could lead to major problems.