Earth’s Rotation During the Late Cretaceous
Recent research has revealed that Earth rotated significantly faster during the late Cretaceous period, around 70 million years ago, completing approximately 372 rotations per year compared to the current 365. This accelerated rotation resulted in shorter days, lasting about 23.5 hours, which is half an hour less than today’s 24-hour day. The findings stem from a detailed analysis of fossilized mollusk shells, specifically rudist clams, which recorded daily growth rings that allowed scientists to count the number of days in a year accurately.
Methodology
The researchers utilized advanced laser technology to analyze the chemical composition of the rudist shells, which exhibited rapid growth patterns influenced by the daily rise and fall of sea levels. This method enabled them to identify daily variations in the shell’s structure, providing a clear count of the growth rings that corresponded to days.
Implications
The study not only sheds light on the Earth’s rotational dynamics during the time of the dinosaurs but also has broader implications for understanding the Earth-Moon relationship. The faster rotation and shorter days indicate that the gravitational interactions between Earth and the Moon have evolved over millions of years, contributing to the current gradual slowing of Earth’s rotation due to tidal friction caused by the Moon’s gravitational pull.
Conclusion
This research enhances our understanding of the geological and astronomical history of Earth, offering insights into how the Moon’s distance from Earth has changed over time. The findings may also provide valuable data for refining models related to climate change and the evolution of marine ecosystems in the past.
Read More
[1] https://www.forbes.com/sites/davidbressan/2020/03/10/dinosaur-days-were-half-an-hour-shorter-than-today/
[2] https://www.sciencedaily.com/releases/2020/03/200309135410.htm
[3] https://edition.cnn.com/2020/03/13/world/early-earth-shorter-day-scn/index.html
[4] https://www.reddit.com/r/askscience/comments/ur1b50/what_caused_the_earths_rotation_and_what_dictated/
[5] https://tarpits.org/sites/default/files/2019-05/la_brea_and_beyond_2015._nhm_science_science_no._42.pdf
[6] https://www.enn.com/articles/62608-ancient-shell-shows-days-were-half-hour-shorter-70-million-years-ago
[7] https://forums.rabidbadger.io/forum/news-and-information/science-and-technology/201481-ancient-shell-shows-days-were-half-hour-shorter-70-million-years-ago
[8] https://sg.news.yahoo.com/70-million-years-ago-days-were-half-hour-035906710.html
