Spaghettification

A simple example

The concept can be illustrated with four objects in space above a planet, positioned in a diamond formation. The force on each object is directed towards the planet's center. In accordance with the inverse-square law, the lowest of the four objects experiences the biggest gravitational acceleration, and two objects on each side are pulled towards each other, so that the whole formation becomes stretched along the line to the planet and compressed transversely.

If these four objects are connected parts of a larger rigid object, then it will resist distortion. Internal elastic forces develop as the body distorts to balance the tidal forces, to maintain mechanical equilibrium. If the tidal forces become too large, the body may yield creating a narrow line of broken pieces.

The forces responsible for spaghettification are called tidal forces. The radial tidal force across an object of mass m and size ${\displaystyle \mathrm{\Delta }r}$ at a distance r from an object of mass M can be estimated with Newton's law of gravity: $${\displaystyle \mathrm{\Delta }F=\mathrm{\Delta }r\frac{2GmM}{r^3}}$$ where G is the gravitational constant.