Final answer:
The Sun's core reaches temperatures of around 15 million K, enabling nuclear fusion of hydrogen into helium and releasing tremendous amounts of energy.
Step-by-step explanation:
The core of the Sun is a region of extreme temperatures and intense nuclear activity. Here, the temperature reaches up to approximately 15 million K (or kelvin), which is essential for the process of nuclear fusion. This temperature is so high that protons, which normally repel each other due to their positive charge, can overcome their electrical repulsion and fuse together. The primary fusion reaction within the Sun's core involves hydrogen atoms, which combine to create helium, liberating vast amounts of energy in the process. Despite forming less than 10% of the Sun's volume, the core generates nearly all the Sun's energy.
At this immense core temperature, the average kinetic energy of particles is equivalent to being accelerated through a voltage of several tens of millions of volts. Outside the core, energy moves outward by radiation up to about 70% of the way to the surface. Thereafter, convection takes over, circulating energy through rising columns of hot gas which continue the energy's journey to the surface. Each second, about 600 million tons of hydrogen undergoes fusion in the core, with 4 million tons being converted into energy, illuminating our solar system.