A most spectacular display of fusion energy is associated with stars, where confinement comes about because of the gravitational pressure of an enormous mass. High density and temperature thereby result toward the stellar centre enabling the fusile ions to bum. While energy leakage and particle escape occurs from the star’s surface, the interior retains most of the reaction power and prevails against the occurrent radiation pressure through the deep gravitational potential wells, thus assuring stable confinement for times long enough to bum most of the stellar fusionable inventory.

Since fusion-powered stars possess dimensions and masses of such enormity, it is evident that confinement by gravity cannot be attained in our terrestrial environment.