On July 29, the Earth broke its record for the shortest day.

It completed a full spin in 1.59 milliseconds less than its standard 24-hour rotation.   

According to the Independent, the planet recently has been increasing its speed. 

Back in 2020, the Earth saw its shortest month that has ever been recorded since the 1960s. 

On July 19 of that year, the shortest of all time was measured.  

It was 1.47 milliseconds shorter than a typical 24-hour day.  

The next year, the planet continued to spin at a generally increased rate, but it did not break any records. 

However, according to Interesting Engineering (IE), a 50-year phase of shorter days may be starting right now.  

The cause of the differing speed of Earth's spin is still unknown.  

But scientists speculate that this could be because of processes in the inner or outer layers of the core, oceans, tides or even changes in climate. 

Some researchers think that this could be related to the movement of Earth's geographic poles across its surface, known as the "Chandler wobble".  

The negative leap second would have potentially confusing consequences for smartphones, computers and communications systems. 

The leap second "mainly benefits scientists and astronomers" but that it is a "risky practice that does more harm than good".

This is because the clock progresses from 23:59:59 to 23:59:60 before resetting to 00:00:00.  

A time jump like this can, therefore, crash programmes and corrupt data due to the timestamps on the data storage.