Here's Why Earth Had 21-Hour Days 600 Million Years Ago

There are new revelations in science every day. Recently, a discovery has been made that will surely surprise you. How many hours in a day to complete a full day? You can easily answer this question – 24 hours. Back to 600 million years ago, when the day was not counted for 24 long; it was just 21 hours in a day.

You might not believe me at first. But let me tell you about a scientific study that will help you understand and believe this. A day is 24 hours long, which equals 86,400 seconds.

Back Then, a Day Lasted Only 21 Hours

The time it takes for the Earth to complete one rotation on its axis is known as the 24-hour day. However, Earth does not rotate uniformly. But Earth's rotation is not constant. The Earth's rotation is gradually slowing down, which results in an increase in day duration of roughly 1.8 milliseconds per century. This means that 600 million years ago, a day was only 21 hours long.

How did the change happen?

The duration of the day has changed over time for a number of reasons. These include the Earth's core-mantle coupling, the Moon and Sun's tidal effects, and the planet's mass distribution. The duration of the day is also influenced by the Earth's magnetic field, weather, oceans, glaciers, and seismic activity (earthquakes).

Study revealed in 2020

In 2020, scientists made a surprising discovery. It had started rotating faster rather than slowing down. Earth is now spinning faster than at any time in the past 50 years. Previously, it was believed that Earth’s rotation was gradually slowing, but this study revealed that it is currently speeding up.

What impact will this have on life?

What is causing this acceleration in Earth's rotation is still a mystery to scientists. Some have suggested that it might be caused by the 20th-century glacier melting or the buildup of a significant amount of water in the glaciers of the Northern Hemisphere. However, experts believe this acceleration is likely temporary. In the coming future, Earth is expected to slow down again.

But now the question arises – should we be concerned for the time being? Although this change will not impact our daily lives, it could have serious effects on technologies like GPS satellites, smartphones, computers, and communication networks, which all rely on highly precise time systems. However, such problems can be managed.  No, unless human action is to blame for the day's shortening, we shouldn't be concerned.