A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time, to accommodate the difference between precise time and imprecise observed solar time.

What is meant by leap second?

A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC), to accommodate the difference between precise time (as measured by atomic clocks) and imprecise observed solar time (known as UT1 and which varies due to irregularities and long-term slowdown in the Earth's ...

How long is a leap second?

It is generally kept between 0.4 and 0.6 seconds. The International Earth Rotation and Reference Systems Service (IERS) in Paris, France, is responsible for monitoring the Earth's rotation and deciding when a leap second is to be inserted.