Key Physics Concepts Behind Earth’s Rotation and Its Effects
While the probability of our planet stopping to spin seems to be almost zero, a slight possibility does exist and paves the way for us to develop the probable theories around the consequences of such a case occur. The fact that earth has seen a constant daytime consisting of 24 hours is only in between the brackets of human knowledge. What was the speed of earth several millennia ago, and what will it be after a plentiful of millennia down the line are questions not known. Scientists have been drawing quite a few plausible theories to predict what lies ahead for the fate of our planet.
The good news is that we wouldn't fall off if the Earth's rotation halted. We could walk on land around the entire equator if water was driven to the poles, but it would be a harsh environment.
We already know that the Earth's rotation is slowing down. But what would happen if our planet's axis of rotation came to a complete stop? Fortunately, geographers can now provide us with the answers, thanks to advances in our understanding of our world. You could go around the world on the equator and keep completely dry, ignoring the bitter cold at night and the scorching heat during the day.
The first thing we may notice is that the Sun no longer travels across the sky in a day. Because Earth's rotation causes the Sun's apparent motion, a single day would last half a year if the planet were stationary (though we could look forward to some very long-lasting sunsets).
What Happens if the Earth Stops Rotating
Currently, what is known to us, is that the planet is slowing down at a rate of 1.7 milliseconds per century. It is believed that this is due to the moon's tidal effect on the planet. If the earth stops rotating all of a sudden, then the atmosphere present around the planet would still be intact at the current earth's speed of 1100 miles per hour at the equator. With the earth at a standstill and the atmosphere in rotation, it would result in all the masses on earth getting uprooted, circling around the planet, and land at another spot across the planet.
For example, a young man is driving on a highway for leisure on a bright and sunny day. He passes a cluster of restaurants a little distant from him. If the earth were to suddenly cease its spin then, this young man would see him, his car, the road, the vegetation around him, the restaurants, and everything and everyone in them flying into the air. As of now, the fastest wind ever recorded is 253 miles per hour, but the wind is almost four times as strong, hence the scenario would be just as deadly.
In addition to this, since the earth bulges at the poles due to centrifugal force experienced by the planet, all the ocean's water would flow towards them leaving a massive single continent at the equator. Due to the overflowing water several parts of North America, Europe, Asia, Australia, South America, and most of the arctic regions would be submerged. This would leave the equatorial and tropical regions to experience drought and the existing life (if any left) would be deprived of food and water due to lack of vegetation.
The natural transition between seasons would also be inhibited due to the year-long day. The final and most fatal consequence would be the loss of the magnetic field of the earth. The earth's magnetic field plays an important role in blocking the sun's deadly cosmic rays, in the absence of it, our atmosphere would pave way for these high-frequency rays to enter the earth's atmosphere, and destroy any life that is left on the planet.
Biological circadian rhythms would be thrown entirely out of whack if we didn't have the 24-hour days we're used to. Regular fluctuations in sunlight are necessary for the rhythmic cellular mechanisms that instruct our bodies when to sleep and wake up to function. Many animals on the planet, from bees to trees, rely on circadian rhythms to function. Changing these cycles may cause standard behavior patterns to be disrupted.
(Image to be added soon)
If Earth Stops Rotating Gradually
On the other hand, if the rotation of the earth is gradually decreased over billions of years, to around one rotation for 365 days resulting in a condition called, 'sun-synchronous,' then the scenario would be quite different. The chances of occurrence of this possibility are pretty high in comparison to the earlier. In this case, a portion of the planet would have perennial sunlight while another would be in constant darkness. This is not exactly the termination of the rotation of the planet, but it is quite close.
In the impossible scenario, six months in sunlight and six months in the night what happens when the earth stops rotating altogether. The winds would alter and the circulation would be in between the poles rather than the currently existing east to west. Adding to this effect, if the earth stops rotating altogether the temperatures on earth would also alter and the equatorial regions would be much hotter and the regions near the poles would be much colder due to the slant rays of the sun are exposed to.
Planets of the Endless Day
There aren't any planets out there that don't revolve at all, as far as we know. Planets and other celestial bodies are formed by natural processes that result in rotation; therefore, all worlds spin from the start. However, other planets appear stationary, which astronomers refer to as tidal locking.
These worlds always display the same face to their star, resulting in night and day sides that never change. Planets' rotation rates can be gradually slowed by gravitational interactions with their stars until they precisely match their orbital period.
Do you mean all at once? You'd be dead in a matter of seconds if the Earth suddenly stopped rotating right now. You'd be thrown sideways at speeds of over 1000 mph, rolling, falling, and sliding down the ground until you collided with something more substantial than you, and then you'd be dead!
After that, you'd be too preoccupied to notice that one side of the Earth, the dayside, would become enormously hotter, while the other side, the night side, would become much cooler. But, before all of that, massive expanses of land would be swept clean by ocean water walls. They aren't speeding up; the Earth has stopped spinning, and conservation of motion keeps anything that isn't glued down firmly to the surface going at the previous spin speed.
FAQs on What Happens If the Earth Stops Rotating?
1. What would be the most immediate and catastrophic effect if the Earth suddenly stopped rotating?
The most immediate effect would be due to inertia. Everything not securely anchored to the Earth's bedrock—including the atmosphere, oceans, buildings, and people—would continue moving at the Earth's original rotational speed, which is over 1,600 km/h at the equator. This would create winds and tsunamis of unimaginable force, instantly scouring the planet's surface and destroying all structures.
2. Is it physically possible for the Earth to stop rotating?
A sudden stop is considered physically impossible due to the law of conservation of angular momentum. The Earth possesses immense rotational momentum, and there is no known force capable of halting it instantly. However, the Earth's rotation is gradually slowing down over billions of years due to the Moon's tidal forces, but this process is incredibly slow and will not lead to a full stop for many billions of years.
3. How would the day-night cycle and global temperatures change on a non-rotating Earth?
If the Earth stopped rotating on its axis but continued to revolve around the Sun, a single 'day' would last an entire year. This would result in:
- One hemisphere facing the Sun for six continuous months, leading to scorching temperatures capable of boiling oceans.
- The other hemisphere experiencing six months of darkness and unimaginably frigid temperatures, freezing gases out of the atmosphere.
- A narrow 'twilight zone' between these extremes would be the only area with potentially survivable temperatures, but it would be battered by constant, violent storms.
4. What is the difference between Earth's rotation and its revolution, and what would happen if it stopped revolving?
Rotation is the Earth's spin on its own axis, which causes the 24-hour day and night cycle. Revolution is the Earth's orbit around the Sun, which takes approximately 365 days and causes the seasons. If the Earth stopped revolving, its forward orbital velocity would become zero. With no velocity to keep it in orbit, the Sun's immense gravitational pull would be unopposed, causing our planet to fall directly into the Sun.
5. If the Earth stopped spinning, would gravity be affected?
No, the fundamental force of gravity would not disappear, as it is dependent on mass, not rotation. However, the apparent force of gravity we feel would slightly increase, especially at the equator. The Earth's spin creates a slight outward centrifugal force that counteracts gravity. Without this force, a person at the equator would feel slightly heavier, but the change would be minor and not the primary catastrophic effect.
6. How would a halt in Earth's rotation affect its magnetic field?
Earth's magnetic field is generated by the geodynamo effect, which relies on the movement of the liquid iron in the outer core as the planet rotates. If the Earth stopped rotating, this process would cease, and the magnetic field would collapse. Without this protective shield, Earth would be fully exposed to deadly solar winds and cosmic radiation, stripping away our atmosphere and making life impossible.
7. What are some examples of how our climate and geography would change if the Earth started rotating backwards?
If the Earth rotated from east to west, the Sun would rise in the west and set in the east. This reversal would have profound effects on climate and geography:
- Ocean currents, like the Atlantic Meridional Overturning Circulation (AMOC), would reverse, completely altering global heat distribution.
- Wind patterns would flip, changing weather systems worldwide.
- Deserts like the Sahara might become lush and green, while verdant regions like the Amazon rainforest could turn into arid landscapes.
8. How does the Earth's rotation influence its shape and the distribution of oceans?
The Earth is not a perfect sphere; it is an oblate spheroid, meaning it bulges at the equator. This bulge is a direct result of the centrifugal force from its rotation. If the rotation stopped, this force would vanish. Gravity would pull the equatorial bulge back, causing the planet to become a more perfect sphere. This would trigger a massive redistribution of water, with the oceans migrating from the equator towards the poles, creating a single massive supercontinent around the equator and two giant polar oceans.
9. Why don't we feel the Earth spinning at incredible speeds?
We don't feel the Earth's rotation for the same reason you don't feel the speed of a car on a smooth highway or an aeroplane in calm air. We are moving at a constant velocity along with everything around us, including the ground, buildings, and the atmosphere. Since there is no acceleration or deceleration, and everything is moving together as one system, we have no sensation of the motion.
10. Would stopping the Earth's rotation for just one second have any major consequences?
Yes, even a one-second halt would be apocalyptic. The issue is not the duration of the stop but the immense and virtually instantaneous deceleration required to stop the planet, followed by an equally violent acceleration to restart it. The resulting forces would unleash destructive shockwaves, earthquakes, and tsunamis far beyond anything imaginable, effectively ending all life on the surface.
