Glittering stars are celestial bodies made up of hot gases, primarily hydrogen and helium. They produce light and heat through nuclear fusion, a process that occurs in their cores. The brightness of a star depends on its size, temperature, and distance from Earth. When we observe stars from our planet, they often appear to twinkle due to the Earth's atmosphere, which causes the light to bend. This phenomenon is known as stellar scintillation. Stars are grouped into constellations, which are patterns that have been recognized and named by various cultures throughout history.