What is the principle of vertical eggs at vernal equinox?

Principle of vertical egg at vernal equinox;

On the vernal equinox, the northern and southern hemispheres are divided equally day and night. The earth's axis is inclined at 66.5 degrees, which is in a relatively balanced state with the earth's orbital plane around the sun, and the earth's magnetic field is also relatively balanced, so the egg stands best.

There are many protrusions about 0.03 mm high on the eggshell, and three protrusions can form a triangular plane. If the center of gravity of the egg passes through this triangle, it can achieve "vertical egg".