Scientists expect that after another 5 billion years, the Sun will have used up its hydrogen energy supply and will begin to burn helium.
At that point, the Sun will likely grow to become a red giant, big enough to encompass the orbit of Mars.
Like other red giants of its size, its outer layer will disperse as stellar wind, leaving its core to cool and dim as a white dwarf.
Eventually, when its core is cold and dark, the Sun will be a black dwarf.
