Edward Roche and Roche Limit

Edward Roche and Roche Limit

Edward Roche

Edward Albert Roche (1820-1883) was born in Montpellier Lière, a French mathematician and astronomer who studied at the University of Montpellier. His most outstanding performance is in the field of celestial mechanics. His name is credited to concepts such as Roche sphere, Roche limit and Roche lobe. .

Historically, Edward Roche's most famous theory is undoubtedly the theory about how Saturn's planetary rings were formed. When a huge moon comes too close to Saturn, it will be pulled apart by gravity. He described a method for calculating the distance at which tidal forces would tear objects together together, a distance known as the Roche limit.

What is the Roche limit?

First of all, from the literal meaning, it is a limit value in a certain aspect. Specifically, it refers to the limit value of a celestial body (usually a small one). The tidal force of another celestial body is a limit value for small celestial bodies to be torn apart by large celestial bodies (often refers to the limit of the distance between them).

In other words, the Roche limit is the distance between one celestial body's own gravity and the tidal force caused by a second celestial body. If the distance between two celestial bodies is smaller than the Roche limit, then the smaller celestial body will tend to fragment or be "torn apart" and then become a ring of the parent celestial body.

In Wandering Earth II, if the moon falls into the Earth-Moon Roche limit, it will be torn apart by the strong gravitational difference when it falls to a certain distance, and it will become many large stars that will hit the earth at high speed. All life and the ecosystem on earth will be destroyed.

Saturn’s Rings and the Roche Limit

The Saturnian Ring is the most prominent and obvious of the planetary rings of the solar system planets. There are countless small particles in the ring, and the main components of the particles are It's all water ice, with some dust and other chemicals. According to research by scientists, the reason for the formation of the ring of the star can be explained by the Roche limit theory: a planet from outside the solar system moved near the star and was torn apart by the huge tidal force of the star, eventually evolving into a ring.