DMasti.Pk

What would happen if Earth stopped rotating but the rest of the universe went on like usual?


if the earth stopped rotating then our whole environment would be gone. No magnetic field, and many other things that would make life as we know it impossible. But it would not affect the rest of the universe. PS: Assuming one sidereal rotation per year, one part of the planet would be hot all the time and the other cold, same with night and day. But this would not fit the requirement of stopped rotation.


Because earth is orbiting a sun, it's literally impossible for it to stop rotating, even in the imagination. If sidereal rotation stopped, which would be the astronomical understanding of 'no rotation', the earth would still rotate once a year relative to the sun, which is after all the center of our solar system. Although this might properly be considered an 'apparent' rotation, and not a 'true' rotation. The day would be one year long and every part of the earth would experience night and day. And most weird, the sun would rise in the west and set in the east. The apparent rotation would be 'retrograde' relative to the other planets. Think carefully about this and you will see that it is true. This scenario is probably impossible as long as the moon continues to exist; the moon would at the very least exert some tidal pull on the earth in the direction of its current rotation.

If on the other hand the earth were tidally locked with the sun (a fate that every sun-orbiting body would eventually succumb to given enough time), the condition assumed in the answer above, then there would be one sidereal rotation per year and the earth's rotation would be analogous to the moon's rotation once per synodic cycle. One face of the earth would always orient toward the sun.

In the tidally locked scenario, there would probably be some serious implications regarding where the moon would have to be and what it's movement would be like. Perhaps the moon would have to be far enough away from earth so that its tidally locked orbit would be equal in length to earth's year, causing the odd situation that observers from earth would always see the same unchanging phase of the moon [see discussion], and the moon would only be visible from one part of earth much the way that earth is only visible from the part of the moon that faces us. And without the gyroscopic orientation that our spin gives us, there would be some serious and hard to predict perturbations in earth's movement caused by neighboring planets and tidal forces from the sun, moon and other bodies. There would still be gravity which is a function of mass, and I don't really have a clue how or if earth's magnetic field would be affected. If the magnetic field is disrupted, then the protection it gives us against bombardment from solar winds/particles would be compromised. Surely, life as we know it would be seriously stressed or ended.