Earth Shortest Day: Earth takes exactly 24 hours to rotate once on its axis. Classic textbook knowledge, right? Well, not anymore. The reality is constantly changing and so are the facts. On July 29, Earth recorded the shortest day, thus establishing the fact that it is spinning faster than its usual speed. The planet completed a full spin in 1.59 milliseconds less than its standard 24-hour rotation. It is interesting to note that this is not the first time that the Earth has quickened its pace. According to a few media reports, Earth recorded its shortest month in the year 2020 and July 19 was recorded to be the shortest day of that year.
Is July 29, 2022, the shortest day in history?
The answer is no. As per various media reports, it has been a few years since Earth started moving faster than before. These reports suggest that July 19, 2020 is to date the shortest day in history as it took the Earth 1.47 miliseconds shorter than usual to complete one spin.
Why is the Earth spinning faster?
Scientists have not yet come to a particular conclusion as to why the earth is spinning faster than its normal speed. However, there are many possible explanations for the same. A study published in Geophysical Research Letters of the American Geophysical Union suggests that global warming has led to significant melting of glaciers due to which our planet’s axis of rotation has been moving faster since the 1990s.
The study further suggests that climate change has also caused the north pole to shift in the eastward direction since the 1990s. This is happening due to changes in the hydrosphere (hydrosphere is the total amount of water on Earth). As per the study, the satellite data from NASA’s Gravity Recovery and Climate Experiment (GRACE) mission calculated that the average speed of drift was 17 times faster than from 1981 to 1995. Also, in the last four decades, the poles moved by about 4 metres in distance.
Consequences: How does it impact us?
According to a report in the Independent, if the Earth continues to rotate at a faster pace, it could lead to the introduction of negative leap seconds. The purpose of introducing these negative leap seconds would be to keep the rate at which the Earth orbits around the Sun consistent with measurements from atomic clocks. This could potentially create a wounding effect for IT systems and software and GPS satellites relying on the clock.