Live Science by Kiley Price 6/18/2023
Days were once five hours shorter than they are now due to the moon's proximity to Earth, a new study suggests.In the prehistoric past, Earth may have been stuck with 19-hour days for a billion years — and the moon was to blame, a new study suggests.
According to the research, published Monday (June 12) in the journal Nature Geoscience, between about 2 billion and 1 billion years ago, a full day lasted five hours less than it does now because of how close the moon lingered near Earth.
Since then, Earth's days have steadily become longer as the moon has distanced itself from our planet, slowing Earth's rotation, according to Live Science's sister site Space.com.
"Over time, the moon has stolen Earth's rotational energy to boost it into a higher orbit farther from Earth," study lead author Ross Mitchell, a geophysicist at the Institute of Geology and Geophysics of the Chinese Academy of Sciences, said in a statement.
However, in the mid-Proterozoic era, the moon consistently hovered at a set distance from Earth, stalling the day length at around 19 hours for 1 billion years before it eventually started getting longer again, the study found. Scientists call this time period the "boring billion" because of the relative stability of Earth's tectonic activity, steady climate and slower biological evolution.
More:
https://www.livescience.com/space/the-moon/for-a-billion-years-earth-may-have-had-19-hour-days-heres-why
