What would happen if Earth stopped spinning?

gif animation showing Earth spinning, there is a little graphic in the top right corner that reads "space mysteries"
If Earth suddenly stopped spinning, it would be catastrophic. (Image credit: AerialPerspective Works via Getty Images)

Even though Earth is always spinning, we can't feel it, and you probably take it for granted. But what would happen if it stopped?

If Earth suddenly stopped spinning, it would be catastrophic. Almost everyone and everything not attached to the planet would continue to move at the current speed of Earth's rotation, around 1,000 mph (1,600 km/h) at its fastest, which is along the equator.

Related: 10 dramatic discoveries about Earth from 20 

"The momentum of all the material that's normally rotating — the water, the air, all the buildings and things like that — would cause them to keep going," said Andrew Layden, a professor of physics and astronomy at Bowling Green State University in Ohio. "So they [would] split off the surface and just keep going around and around, basically, in a low orbit around the Earth."

The only parts of our planet that would likely be less affected would be at or near the poles, which rotate little or not at all. Still, the extreme force would likely trigger tsunamis and earthquakes, so things would be pretty bad for the entire Earth.  

Related: Earth is whipping around quicker than it has in a half-century

If Earth were to slow down and stop more gradually, life would still change drastically. For instance, the length of our days and nights would become longer until each lasted six months. It would also change our weather, Layden said, since air and ocean currents are strongly influenced by Earth's rotation. 

It's possible that a lack of rotation would affect how well life could survive on Earth, said Layden. Our planet generates a magnetic field, which protects us from harmful radiation from space. Scientists think the Earth's magnetic field is linked to flowing liquid metal in our planet's outer core, which generates electrical currents and a resulting magnetic field due to Earth's rotation. Some researchers think that the loss of Mars’s magnetic field in the distant past contributed to the planet becoming uninhabitable, said Layden.  

The good news is that it is very unlikely that Earth will ever stop rotating, scientists say. Every planet we know of rotates, and even stars rotate slowly. Stars form from huge, circling masses of gas and dust that condense together gradually. Because the solar system formed out of a huge disk of debris around the burgeoning sun, the material that formed the solar system was also circling. This is why most planets in the solar system rotate in the same direction.

Planets also spin because objects hit them, often during the planets' formation. Much like billiard balls, unless the objects hit each other head-on, one or both will start spinning.

Getting hit is also one of the only ways a planet might actually stop rotating suddenly, said Layden, or at least have its rotation dramatically slowed. If a very large, planet-size object slammed into our planet — as was the case in the collision that formed Earth's moon, the massive impact might counteract Earth's spin or even cause the planet to spin the opposite way. This might have happened to at least one planet in our solar system.

"Venus rotates very slowly — in fact, very slowly backward compared to Earth and [all of] the other inner, terrestrial planets," Layden said, possibly as a result of such a collision.

Venus rotates slowly 'backward'. (Image credit: ARTUR PLAWGO/SCIENCE PHOTO LIBRARY/Getty Images)

Uranus also rotates in the opposite direction as Earth does, and on its side. Scientists think both Uranus' and Venus' original rotations might have been "stopped" by one large impact, several smaller impacts, or a disruption in their rotations by a large gravitational force. In Venus' case, that might have been the sun's gravitational force on its thick atmosphere; for Uranus, it might have been a large moon that was eventually ejected from its orbit

Luckily, our planet's rotation isn't in danger of being disrupted by a huge gravitational force, and if Earth were colliding with a planet-size object, we'd have bigger things to worry about. Still, Layden said, this scenario is vanishingly unlikely in our modern solar system, where planets' orbits are pretty regular and unlikely to cross paths with massive objects.

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Rebecca Sohn
Contributing Writer

Rebecca Sohn is a freelance science writer. She writes about a variety of science, health and environmental topics, and is particularly interested in how science impacts people's lives. She has been an intern at CalMatters and STAT, as well as a science fellow at Mashable. Rebecca, a native of the Boston area, studied English literature and minored in music at Skidmore College in Upstate New York and later studied science journalism at New York University. 

  • geowin
    Admin said:
    We can't feel Earth spinning and you probably take it for granted, but what would happen if it stopped spinning? We take a look at the disastrous impacts it would have.

    What would happen if Earth stopped spinning? : Read more
    Did Professor Layden of BGSU really suggest in this article that an object leaving earth’s surface at a maximum speed of around 1,000mph (earth’s rotational speed at the equator) will go into ‘low earth orbit’? Gosh, with the apparent lower Earth escape velocity in Ohio, NASA could save a fortune by moving their launch facilities there. Added bonus: they could also use standard AR-15 bullets to shoot down any overhead spy satellites.
    Reply
  • Unclear Engineer
    This article is rather silly, trying to conceptualize the Earth's spin to stop in some manner that does not stop what is on the surface, so that things at the equator suddenly have 1,000 mph relative velocity to the east. Why would the surface rock layer stop? Why would the oceans not stop? The whole scenario is just physically ridiculous, so describing the results based on physics is a non-sequitur.

    But, the article then gets somewhat more rational in discussing the rotation rates of other solar system bodies, and how collisions might have caused what we now observe.

    Which reminded me of the old "Worlds in Collision" theory of Immanuel Velikovsky, which had Venus going past Earth to cause events in our history.

    But, what about Venus taking the place of "Theia", and, instead of melding with Earth in a collision, Venus had its rotation nearly stopped while Earth's rotation was increased and the debris left in Earth's orbit by the collision becomes our Moon?

    And, extending on that, what would the effect of climate be for an almost-not-rotating planet (Venus) somewhat closer to the Sun that Earth? Could the lack or rotation be the cause of the vastly different climate evolution, compared to Earth?

    Those thoughts seem to be a lot more worthy of some speculative thinking than the idea about what would happen if the Earth's rotation would suddenly stop.
    Reply
  • Pogo
    And imagine the effects on the internals of the planet itself, suddenly stopping some 6x10^24 kg.
    Then the most humongous tsunami as the sea sloshes around the Earth a few times.
    And the moon will stop receding as the Earth’s rotation will no longer drag the tMoon in its orbit, but, the Moon continuing to orbit will drag the Earth into beginning to rotate again slowly, then the moon’s orbit will begin to approach the Earth, albeit very slowly.
    That may be not so good.
    Reply
  • Helio
    Unclear Engineer said:
    This article is rather silly, trying to conceptualize the Earth's spin to stop in some manner that does not stop what is on the surface, so that things at the equator suddenly have 1,000 mph relative velocity to the east. Why would the surface rock layer stop? Why would the oceans not stop? The whole scenario is just physically ridiculous, so describing the results based on physics is a non-sequitur.
    Agreed. Either it stops or it doesn't. But if the surface, for some reason, doesn't suddenly stop, as geowin notes, the 1000mph velocity won't put stuff in Earth's orbit around the Sun. It's not a momemtum issue but an escape velocity one.
    Unclear Engineer said:
    But, the article then gets somewhat more rational in discussing the rotation rates of other solar system bodies, and how collisions might have caused what we now observe.
    Yes, that was interesting.
    Unclear Engineer said:
    But, what about Venus taking the place of "Theia", and, instead of melding with Earth in a collision, Venus had its rotation nearly stopped while Earth's rotation was increased and the debris left in Earth's orbit by the collision becomes our Moon?
    Yes, but there's all the other objective arguments for an impact, including the great similarity of composition, the size of the Moon, the size of our core, etc. The Theia model, like so many other nascent models, originally was very unaccepted.

    Unclear Engineer said:
    And, extending on that, what would the effect of climate be for an almost-not-rotating planet (Venus) somewhat closer to the Sun that Earth? Could the lack or rotation be the cause of the vastly different climate evolution, compared to Earth?
    That's logical. Apparently, a lot has to do with the winds of their atmospheres, which are needed for heat transfer. Then there are some views about habitability in the transition zones of night and day.

    I have a question that has bugged me for quite a while. We learned from Planck (probe) that the Earth generates a spacetime drag so that there is some rotation of spacetime around a rotating body. I think it's called frame-dragging.

    But, being a Newton fan perhaps, if the Earth an cause frame-dragging, would not frame-dragging of spacetime in turn affect the rotation rate of a body, assuming one could do this to spacetime around it? If so, would there be any catastrophic effects on the surface in the short term?
    Reply