{"id":36021,"date":"2026-08-29T10:15:00","date_gmt":"2026-08-29T14:15:00","guid":{"rendered":"https:\/\/ecoticias.com\/en\/?p=36021"},"modified":"2026-08-29T10:15:00","modified_gmt":"2026-08-29T14:15:00","slug":"earth-may-have-spent-roughly-a-billion-years-with-days-stuck-near-19-hours-long-and-scientists-think-an-extraordinary-tug-of-war-involving-the-moon-and-the-atmosphere-temporarily-stopped-the-planet","status":"publish","type":"post","link":"https:\/\/www.ecoticias.com\/en\/earth-may-have-spent-roughly-a-billion-years-with-days-stuck-near-19-hours-long-and-scientists-think-an-extraordinary-tug-of-war-involving-the-moon-and-the-atmosphere-temporarily-stopped-the-planet\/36021\/","title":{"rendered":"Earth may have spent roughly a billion years with days stuck near 19 hours long, and scientists think an extraordinary tug-of-war involving the Moon and the atmosphere temporarily stopped the planet\u2019s rotation from slowing normally"},"content":{"rendered":"\n

Two studies that were published in 2023 argued that our planet went through a massive stagnation<\/a> during the Proterozoic, when Earth’s rotation got stuck between 19 and 19.5 hours for about a billion years.<\/p>\n\n\n\n

But also there was a review in 2024<\/a> that questioned both the geological evidence and the physical theories behind those studies. Additionaly, another study in 2026 estimated days of about 17.7 to 17.9 hours about 1.787 billion years ago.<\/p>\n\n\n\n

The Moon keeps applying the brakes<\/h2>\n\n\n\n

The Moon does much more than only moving and \u201ccontrolling\u201d the sea tides. It also gradually slows the Earth’s rotation. Because of this energy transfer, the Moon is pushed away from us by about 3.78 centimeters per year today<\/a>.<\/p>\n\n\n\n

Even so, scientists say we cannot just apply today’s speed to the past. Continents, ocean depths, and coastlines have constantly shifted over time, changing how that energy is lost.<\/p>\n\n\n\n

\"Earth
Earth appears above the lunar horizon in a NASA image, a striking view of the two worlds whose gravitational interaction has changed Earth’s rotation over time.<\/figcaption><\/figure>\n\n\n\n

The Sun may have pushed back<\/h2>\n\n\n\n

Sunlight warms the atmosphere unevenly and that actually generates enormous pressure waves. If the duration of half of the day approached the natural resonance of the atmosphere, those waves would strengthen enough for solar gravity to pull Earth forward and speed it up. That is the main explanation for the \u201c19 hours theory\u201d.<\/p>\n\n\n\n

How rocks remember a day<\/h2>\n\n\n\n

Scientists can know how long a day lasted in the past with the use of geological documents and archives since they included information about tidal rhythmites, stromatolites, and cyclostratigraphy that preserve daily, seasonal, and orbital patterns.<\/p>\n\n\n\n

However, there are other theories that say that maybe that was not possible. In fact a 2024 review concluded that this 19-hour theory depended a lot on uncertain stromatolite evidence.<\/p>\n\n\n\n

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