Do you ever wish there were more than 24 hours in a day? It turns out, there was a time when Earth’s days were much shorter. Around 4.5 billion years ago, when the Moon first formed, there were fewer than 10 hours in a day. But over time, Earth’s rotation slowed down due to lunar tidal forces. However, there was a fascinating period when days didn’t grow at all. From 2 billion to 600 million years ago, multiple tidal forces canceled each other out, keeping Earth rotating at the same speed for over a billion years. If that hadn’t happened, our days might be over 65 hours long today.
“The fact that the day is 24 hours long…is not a coincidence,” says a research team in a study published in Science Advances.
Giving it a spin
So, how do tidal forces from the Sun and Moon affect Earth’s spin? The Moon’s gravitational pull generates lunar tidal forces, causing bulges on the side of our planet closest to and furthest from the Moon. These bulges create high tides in the oceans and resist Earth’s spin. As the Earth rotates, the sites of these bulges change, creating friction that slows down rotation.
There are two types of solar tides that also affect rotation. The first is solar tidal torque, which operates similarly to the Moon’s tidal forces, slowing down Earth’s spin. The second is thermal tidal torque, caused by sunlight heating the atmosphere and expanding it. This creates another handle for the Sun’s gravity to interact with, pushing Earth to rotate faster. Although the Sun’s gravity is more powerful, the Moon’s tidal forces generate twice the force due to its proximity. As a result, days continue to grow slightly longer.
A period of stasis
Two billion years ago, everything changed. Earth’s atmosphere was warmer, affecting the thermal waves created by sunlight. Higher temperatures increased wave velocities, creating an atmospheric resonance that amplified their effect. For a billion years, this resonance and the length of the day remained in sync, with atmospheric waves resonating every time Earth completed about half a rotation.
Because Earth’s rotational period was almost exactly double that of the resonance period, the Sun’s tidal forces became stronger, countering the lunar tides. Earth ended up moving at the same speed, neither slower nor faster. Days wouldn’t grow longer again until 600 million years ago, a billion years after the resonance began.
The study’s team confirmed their computational models by examining geological evidence of ancient rock formations, which showed high and low tides. “The long duration and relatively recent occurrence of this resonant state may be responsible for the fact that the day is currently 24 hours long,” the astrophysicists stated in the study.
Could rising temperatures from global warming further disrupt the resonance and lengthen days? It’s happening right now. The more out of sync resonance and rotation become, the less solar tidal forces can counter the lunar tidal forces that have gradually extended Earth’s days over eons. While we might all appreciate a few extra hours in the day, we shouldn’t sacrifice our planet for it.
Science Advances, 2023. DOI: 10.1126/sciadv.add2499 (About DOIs).
Elizabeth Rayne is a creature who writes. Her work has appeared on SYFY WIRE, Space.com, Live Science, Grunge, Den of Geek, and Forbidden Futures. When not writing, she is either shapeshifting, drawing, or cosplaying as a character nobody has ever heard of. Follow her on Twitter @quothravenrayne.
It is no secret that long work days can lead to an increase in stress levels, fatigue, and a decrease in productivity. For workers, this often results in a difficult cycle in which extended work days become the norm, leaving little or no time for family or leisure activities. With the ever-growing need for productivity and efficiency in the workplace, a solution is needed to alleviate the burden of long workdays. The answer may lie in the concept of gravitational interactions.
Gravitational interactions involve the pull of two objects that are attracted to each other. This pull is often influential in how objects interact with each other, such as in the case of galaxies or in our everyday lives. With regards to the workplace, gravitational interactions can be used to motivate employees, leading to a more productive and efficient work environment.
Gravitational interactions provide three primary benefits in the workplace: increased collaboration, expedited task completion, and improved employee satisfaction. When employees are able to collaborate and work together on a project, the overall quality of the finished product is improved. This collaboration can also lead to expedited project completion, as one employee may be able to fill in the gaps of another’s knowledge or expertise, leading to a faster task completion. Finally, the satisfaction increases when employees can complete tasks quickly, reducing the amount of time that needs to be dedicated to the task or project. This can lead to increased job satisfaction, helping to avoid burnout and fatigue in the workplace.
By utilizing gravitational interactions, employees benefit from improved collaboration, expedited task completion, and heightened satisfaction. With these benefits in mind, it is easy to see how gravitational interactions can help to avoid 60-hour workdays, leading to a healthier, happier, and more productive workforce.
