Evolution of low-mass stars

Stars which have a mass of less than 80% the mass of our Sun are classified as low-mass stars. Like all stars, they are born in dense molecular clouds. Because of their low mass they burn their fuel slowly — allowing them to exist for billions of years. The lower the mass of a star, the longer the lifespan. In fact, the Universe is not old enough yet for a low-mass star to die. As the hydrogen is burned in a low-mass star, the rate of fusion declines and the core starts to contract. While stars with 25% the mass of the Sun will become red giants — and later on into white dwarfs — the ones with even less mass evolve into blue dwarfs and finally white dwarfs. After trillions of years white stars eventually cool down and no longer glow: they become black dwarfs. This graphic will form part of the "The Living Universe" exhibition, to be displayed at the ESO Supernova.