How to understand the strength of planetary energy

E = MC 2 (energy = mass × velocity squared). Mass is determined by gravity, assuming that the planetary gravity is not zero, then m ≠ 0; Therefore, it is inferred from the formula that c=0. In other words, when the planet's energy is equal to 0, it will not do any motion (relatively static).

An ellipse has two focuses, and the centripetal force will only move to one of them. When the star is in one of the focuses, the planet will get a centripetal force (attracted by the gravity of the star). As long as it runs to the star and moves in a straight line at a uniform speed, when the planet approaches the star, it will be influenced by the gravity and acceleration of the star and move around the star, thus generating a driving force to push the planet to another focus of the elliptical trajectory. When the acceleration of the star returns to zero, the planet will rush to the star again (just like throwing a ball into the air, the ball will be in air movement under the action of acceleration, and when the acceleration returns to zero, it will fall due to the influence of the gravity of the earth), naturally forming an elliptical trajectory. So, as long as c≠0, that is, E≠0, the trajectory of the planet will be