The Sun, like all stars, has a life cycle. Currently, it is in the "main sequence" stage, where it has spent about 4.6 billion years converting hydrogen into helium through nuclear fusion. This phase will last approximately another 5 billion years. As the Sun depletes its hydrogen, it will enter the red giant phase, expanding significantly and engulfing the inner planets, possibly including Earth. During this phase, its outer layers will cool and glow red. Eventually, the Sun will shed its ou...