The primary color of the sun’s core is a deep blue, though it appears colorless to the human eye due to the extreme temperatures and pressures present. The sun's core, where nuclear fusion occurs, reaches temperatures of about 15 million degrees Celsius (27 million degrees Fahrenheit). In this extreme heat, hydrogen nuclei fuse to form helium, releasing vast amounts of energy in the process. This energy radiates outward, contributing to the light and warmth we experience on Earth. The sun's outer layers appear yellow or white depending on perspective, but the intensely hot core produces energy predominantly in the blue spectrum.