Earth's magnetic field, generated by the motion of molten iron in the planet's core, would be significantly affected if Earth's rotation suddenly stopped. The geodynamo that produces the magnetic field relies on Earth's rotation, so a halt in rotation would likely lead to a weakening or collapse of the magnetic field over time.12 This would have severe consequences, as the magnetosphere shields Earth from harmful solar radiation and cosmic rays. Without this protective "bubble," the planet would be exposed to increased levels of particle radiation, potentially damaging satellites, disrupting communications systems, and posing risks to life on the surface.23

The weakening of the magnetic field could also result in more frequent geomagnetic storms and auroras, as solar wind particles would more easily penetrate the atmosphere.3 Additionally, the loss of the magnetic field's protective properties could lead to atmospheric erosion over time, similar to what occurred on Mars when it lost its magnetic field.2

The sudden halt of Earth's rotation would have severe consequences for satellite technology, disrupting crucial services that modern society relies on. Satellites in geostationary orbit, which maintain a fixed position relative to Earth's surface, would suddenly find themselves out of sync with the planet's new rotational state1. This misalignment would disrupt communications, weather forecasting, and navigation systems that depend on these satellites2. Low Earth orbit satellites would also be affected, potentially altering their orbits and increasing the risk of collisions with space debris3. The weakening of Earth's magnetic field resulting from the rotational stoppage would expose satellites to higher levels of solar radiation, potentially damaging their electronics and shortening their operational lifespans4. These disruptions would have far-reaching impacts on daily life, affecting everything from GPS navigation and internet connectivity to weather prediction and disaster management capabilities5.

If Earth's rotation suddenly stopped, ocean currents and global geography would undergo dramatic changes. The cessation of rotation would disrupt the Coriolis effect, which plays a crucial role in driving ocean currents and atmospheric circulation patterns1. Without this force, major ocean currents like the Gulf Stream and the Kuroshio Current would weaken or cease, significantly altering global climate patterns2. The equatorial regions would likely become much hotter, while higher latitudes could experience severe cooling3.

The redistribution of water masses would reshape coastlines and alter sea levels. As the centrifugal force diminishes, oceans would shift towards the poles, potentially submerging polar regions and exposing new land masses near the equator1. This massive redistribution of water would cause catastrophic flooding in some areas and create vast new deserts in others, fundamentally altering Earth's geography and ecosystems3. The changes in ocean circulation would also impact marine life, disrupt global weather patterns, and have far-reaching consequences for agriculture and human habitation patterns across the planet45.