On Tuesday the day is imperceptibly longer than usual, as it will add one second.
“The Earth’s rotation is slowing somewhat gradually, so this extra second realizes that, “said Daniel MacMillan, the Goddard Space Flight Center in Greenbelt, Maryland. A day lasts exactly 86,400 seconds.
However, the average solar day is what it takes for the Earth to make one complete rotation is about 86400.002 seconds. This is because this rotation is slowing gradually, due to forces that slow as the gravitational pull between the Earth, Moon and Sun. Scientists estimate that the last time that day lasted exactly 86.4 thousand seconds was about 1820.
This difference of two milliseconds, much less a note not blinked. But when it is repeated daily for a year it becomes almost a second.
The day length is influenced by several factors, notably atmospheric type as those produced by El Niño. Other factors contributing to this are groundwater and ice.
Scientists monitor what it takes Earth to complete rotation using an extremely precise technique called “Very Long Baseline Interferometry”. These measurements are made through a network of global stations, which are coordinated by Goddard, which also analyzed and the data are archived.
With this information, you decide to add a second when necessary, determination making the Service and Reference Systems International Earth Rotation. The second to be added is not something you can predict a long time, so it was elegico insert the June 30 or December 31.
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