What If Earth Stopped Spinning? What Science Says Happens

What if Earth stopped spinning? If it stopped suddenly, the atmosphere and anything not anchored to bedrock would keep moving east at up to about 1,670 km/h at the equator, causing catastrophic winds. If it stopped slowly, oceans would shift toward the poles and one day would last a full year. Both are extremely unlikely.

This is a thought experiment. Earth's spin is slowing only by tiny amounts over millions of years.

How fast is Earth spinning?

Earth rotates once about every 24 hours relative to the Sun and every 23 hours 56 minutes relative to the stars. At the equator that is roughly 1,670 km/h, falling to zero at the poles.

What if Earth stopped spinning suddenly?

The ground would stop, but the air, water and anything not attached would not. Space.com and Astronomy magazine describe winds of more than 1,000 mph (about 1,600 km/h) at the equator, collapsing structures, and likely tsunamis and earthquakes. Places near the poles, which barely rotate, would be least affected.

What if Earth stopped spinning slowly?

An Esri ArcUser analysis modelled Earth slowing to a stop over a few decades. Earth's spin creates a bulge of ocean water about 8 km high at the equator. Without spin, the oceans would migrate toward the poles, leaving one huge equatorial megacontinent between two polar oceans.

How long would a day be?

Esri notes that if Earth stopped rotating but kept orbiting the Sun, a day would last as long as a year. Space.com puts it as days and nights each lasting six months.

Would we lose the magnetic field?

Physicist Andrew Layden told Space.com that scientists link Earth's protective magnetic field to flowing liquid metal in the outer core and the planet's rotation, so losing the spin could affect it. This is a hypothesis rather than a measured fact.

FAQ

Can Earth stop spinning? Esri calls it extremely unlikely. Its spin is slowing only very gradually.

Is Earth's rotation slowing? Yes, very slightly, mainly due to tidal friction from the Moon.

Would there be hurricanes? Astronomy magazine notes hurricanes depend on the Coriolis effect from Earth's rotation, so they would end.

Related

• What would happen if the Moon disappeared?
• What is the Fermi paradox?
• What is a Dyson sphere?

Sources

• 01esri.com/news/arcuser/0610/nospin.html
• 02space.com/what-would-happen-if-earth-stopped-spinning
• 03astronomy.com/science/what-happens-if-earth-stops-rotating/
• 04astronomy.com/science/what-would-happen-if-earth-stopped-spinning/
• 05en.wikipedia.org/wiki/Earth%27s_rotation