In our planet’s remote past, days ran in the blink of an eye. A fascinating study carried out by leading scientists from China and Germany has revealed an astonishing finding: some 1 billion years ago, 19-hour days ran on our planet. This extraordinary acceleration of time occurred during the Proterozoic era, a period that spanned from 2.5 billion years ago to 540 million years ago, in the Precambrian epoch. Imagine the dizzying pace of life back then!
They confirm that 19-hour days elapsed.
Days lengthened non-uniformly and steadily from 19 to 24 hours over approximately 1 billion years. This phenomenon is attributed to changes in our atmosphere.
They published the study in Nature Geoscience. It reveals that during that period, tectonic activity ceased, as did the evolution of life. Scientists called it the “boring billion” epoch. During this time, the Earth maintained a constant rotation cycle, with days 19 hours long.
Past that period, the Moon took rotational energy away from the Earth to move away to an orbit farther away from our planet. Because of this lunar drift away, the Earth slowed down and as a consequence, the days lengthened to 24 hours. According to the researchers, the days on Earth have been lengthening at a rate of 0.000015 seconds per year since then, according to Science Alert data. This continues to happen today.
Earth’s rotation models show that the days are lengthening steadily. This has been happening for the last 3 to 4 billion years. According to science, there may have been a period of stability in ancient times, although until today there was no evidence in geology to certify it. However, thanks to this new study, there is.
How did they detect that the days were shorter?
Ross Mitchel, professor at the Institute of Geology and Geophysics of China and Uwe Kirchner of the University of Turbingen in Germany are the authors of the discovery. In addition to data collected in recent years, they used the geological method of cyclostratigraphy. This method is based on the stratification of rhythmic sediments to study the Milankovitch astronomical cycles.
These cycles give insight into how changes in terrestrial orbit and rotation affect climate. In this way they detected that in the past, these cycles were shorter due to the wobble and tilt of the planet’s axis.
They also studied ocean tides and solar tides. In addition to ocean tides that are caused by the Moon, our planet has solar tides.
They are produced by the heating of the atmosphere during the day. These solar tides are much weaker than oceanic tides; however, this was not the case in the past. The ocean tides due to lunar attraction were one-fourth as strong as they are today.
Solar tides were more intense because of ozone injection and the strength of sunlight. According to scientists, this may have been the cause of the thousand years in which the Earth almost stopped its tectonic activity.