The Stellar Life Cycle

A star begins as a cloud of gas and dust that collapses under gravity, forming a dense core called a protostar. Once nuclear fusion starts, it becomes a main sequence star, like our Sun, shining steadily. Over millions to billions of years, depending on its size, it exhausts its fuel. Smaller stars swell into red giants and eventually shed outer layers, leaving behind a white dwarf. Larger stars explode as supernovae, creating neutron stars or black holes. This life cycle illustrates how stars grow, change, and eventually end, enriching space with elements vital for planets and life.