Tonight at some point before 8:00 PM Eastern Time, the world will experience what is known as a "leap second". There will be a minute of time that is 61 seconds long. Today, June 30, will be approximately one second longer than usual, and official atomic timekeeping will factor in this second before turning over to July 1. This strange concept has a fascinating history and explanation; however, it is also a cause of concern for market traders around the world, who fear that this extra second will disrupt global operations.

The leap second phenomenon occurs as a result of two factors: universal atomic timekeeping and the Earth's rotation. 1967 was the first year that official timekeeping was based on an atomic clock, becoming the standard for timing worldwide. This atomic timing is known as UTC, or Coordinated Universal Timing. UTC is kept on a consistent basis; the Earth's rotation, however, does not quite match with it. In fact, the Earth's rotation is gradually slowing down. As a result, actual time drifts off of atomic time by fractions of a second every year. These discrepancies keep adding up year after year, and the scientists who manage UTC make up for this difference by adding a second to the official time every few years. These adjustments usually happen on either December 31 or June 30. The first year a leap second ever occurred was 1972 and there have been twenty-five more since then.

Although they used to occur on a regular basis, there have not been as many leap seconds in the 21st century. When they do happen, it has caused unprecedented problems. Computer systems use NTP, known as Network Time Protocol. NTP has to stay consistent with UTC, and with the addition of an extra second, it is not easy for NTP to stay in sync. When computer systems fail to account for this extra second, glitches occur. The last leap second, which transpired on June 30, 2012, caused the crashes of websites such as Reddit, LinkedIn, Mozilla, and even Qantas Airways, an Australian aircraft carrier. However, these websites were able to soon recover, and there were no other major problems.

This impending leap second spells a more drastic story. It will fall on the normal opening time of many Asian markets and the operating times of other international markets. Now that the majority of markets operate using e-commerce, companies and market analysts are fearful that the leap second will cause a disruption in their trading systems. To avoid this, several markets are planning on either running and shutting down operations before 8:00 PM or starting a little bit after that time. Other websites and operators are seeking a different solution by spreading out the second by additions of milliseconds throughout the day. It is unknown how well these solutions will do to avoid the impact of a leap second, but it is hoped that they will work. If the leap second does end up crashing the computer systems used to manage e-commerce trading, it could prove disastrous for these markets and could seriously disturb important trade and business operations.

A necessary adjustment for the sake of timekeeping has the potential to upend the Internet and international e-commerce. How do you plan on spending your extra second today?

Share this article