In the distant past, a day on Earth lasted 19 hours, not 24 hours as it is now, according to scientists.
The reason for the shorter duration of the day was the position of the Moon, which was closer to the Earth at that time.
A geophysicist at the Institute of Geology and Geophysics of the Chinese Academy of Sciences, Ross Mitchell, explains that the Moon has, over time, “stolen” the Earth’s rotational energy in order to move it further into orbit, that is, further away from the Earth.
Mitchell is the lead author of a study devoted to the length of the day, which was published in the scientific journal “Nature Geosciences”.
The day lasted 19 hours one to two billion years ago, he explains.
Uv Kirscher, co-author of the study and associate of the Australian Curtin University, points out that “most models of the Earth’s rotation indicate that the length of the day was shorter in the past”.
Day length can be determined by cyclostratigraphy – a geological method in which rhythmic sedimentary layers are used to reveal astronomical “Milankovic cycles”, which indicate how changes in the Earth’s orbit and rotation affect the climate.
Milutin Milanković was a Serbian scientist and one of the world‘s greatest climatologists.
“The two `Milanković cycles’ – precession and tilt – are related to the oscillation and tilt of the Earth’s rotation in space. The faster rotation of the Earth in the past is noticeable in the period of shorter precession and tilt,” Kiršer explains.
(Srna)