Leap Seconds: The Great Sync

Since 1972, the International Earth Rotation and Reference Systems Service (IERS) has occasionally added an extra second to the day. This is the **Leap Second**, an administrative hack used to keep our precise atomic clocks (UTC) in sync with the irregular rotation of the Earth (UT1).

The Earth is Slowing Down

Because of the moon's gravity and shifting plates, the Earth's rotation is gradually slowing down. As a result, our atomic clocks eventually "pull ahead" of the sun. When the difference between atomic time and solar time reaches 0.9 seconds, a leap second is added to the very end of June or December.

The IT Nightmare

While a leap second is invisible to humans, it is catastrophic for computer systems. Many servers and databases aren't designed to handle a minute that is 61 seconds long. In the past, leap seconds have caused massive "crashes" for airlines, social media platforms, and financial markets. To avoid this, companies like Google use "Leap Smearing"—spreading the extra second across an entire 24-hour period.

The End of the Leap Second

In 2022, the Bureau International des Poids et Mesures (BIPM) voted to stop adding leap seconds by **2035**. The world will allow the drift between clocks and the sun to grow larger for a longer period, prioritizing the stability of digital networks over astronomical alignment.

Conclusion

Leap seconds represent the tension between human logic and planetary reality. On the Epoch Clock, we follow Unix time, which ignores leap seconds entirely, treating every day as having exactly 86,400 seconds.