What happens when we stop spinning….
The Earth has stopped spinning.
This is what Cost centre 3 posed to me recently in an awe struck tone. By that I believed she meant that literally the Earth stops turning on its axis, but that everything else carries on as normal. For example the Earth would continue to revolve around the Sun. Well as I looked at her (panicked as to how to follow up) that’s what I think she meant.
If the Earth was to stop spinning immediately then Scientists think that life and everything else would be decimated as the oceans, atmosphere, us would continue to move (at 1770km per hour). We would be thrown around and probably swept off the planet. The oceans would move to form tsunami’s across the land and rocks would shift causing earthquakes as nothing would be holding them in check. Nice. Looking forward to that movie.
In a slower deceleration, half of the earth would face the sun and the other half would be in the cold and dark for a large part of the year which could result in boiling or freezing temperatures respectively. Rotation produces a centrifugal force. According to Sciencedirect.com, this force ‘is the apparent outward force on a mass when it is rotated’. Since the Earth rotates around a fixed axis, the direction of centrifugal force is always outward away from the axis. Over billions of years, the centrifugal force combined with slightly stronger gravity has pushed the solid part of the planet, and the oceans outwards meaning that the Earth is lopsided with the diameter at the equator greater than the diameter through the poles due to solid land and water having been pulled into a bulge. However if the Earth stopped rotating there would be no centrifugal force and so with the impact of gravity, the oceans would move quickly away from the equator moving freely across the earth to form oceans at the poles. This would reveal more land at the equator but also potentially put Canada, parts of Asia and Europe under water.
What science isn’t sure about is what happens to the Earth’s magnetic field if the Earth stops spinning — partly because it isn’t known what causes this magnetism. Some think that without the magnetic field we would be more vulnerable to the sun.
This does raise a question we take for granted. Why does the Earth spin? And this is one of those because it does. Or more accurately — because it always did. When the Earth was formed it was a mass of rotating swirls of gases and dust which started to collapse under its own gravity forming our planet But it had very little act on it to slow down the spinning. According to Newton’s first law of motion ‘…..a body at rest will remain at rest, and a body in motion will remain in motion unless it is acted upon by an external force….’. All the planets orbiting the sun rotate for a similar reason and continue to do so because they always have. But the Earth’s rotation around its axis is slowing. When the earth was formed a day was 6 hours long. That meant to rotate around the axis once fully took 6 hours. The Earth’s rotation is getting marginally slower over time due to the moon’s gravity but no one thinks we need to worry about the earth stopping spinning. Unless Cost centre 3 knows something we don’t……
