Stars are massive, glowing spheres of hot plasma (mostly hydrogen and helium) held together by their own gravity. They generate their own light and heat through nuclear fusion in their cores, a process that smashes lighter atoms together to form heavier ones, releasing incredible amounts of energy.

Our Closest Star is the Sun, which provides Earth with the light and warmth required to sustain life.

Stars are born from vast clouds of gas and dust (nebulae). When they eventually exhaust their fuel, they end their lives in spectacular ways, ranging from gently fading into white dwarfs to exploding as massive supernovas. A star’s colour depends on its surface temperature. The hottest stars burn blue, while the coolest ones glow red.