WHEN WILL THE SUN DIE?
A gigantic cloud of gas and dust formed in our galaxy 4.6 billion years ago. Gravitational forces and rising temperatures (10,000,000°C) made the nuclei of hydrogen atoms move so quickly that a nuclear reaction occurred, creating our sun. The star will continue to heat up and expand until, in a billion years’ time, the average temperature on Earth will exceed the critical value of 30°C, killing off most higher forms of life. In five billion years, the sun will become a red giant, having expanded to over 100 times its current size. One billion years later, it will die, cast off its external layers and create a planetary nebula. A hot, dense core of oxygen and carbon one and a half times larger than Earth will remain: a white dwarf.