The end of the Sun: the end of human life? By: Sarah willemssens

At the core of the Sun is enough hydrogen to last 4,500 million years, when hydrogen fuel is spent, the sun will change: as the outer layers will expand to the current size of the orbit of the Earth, the Sun will become a red giant, slightly cooler than today, but 10 000 times brighter because of its huge size.The Sun will remain a red giant, with nuclear reactions of helium burning in the center, for only 500 million years. After the red giant stage, shrinks to be a white dwarf, about the size of Earth, and slowly cooled for several million years. When this catastrophe will happen?