The Sun’s lifecycle will eventually cause Earth to become uninhabitable, but not for billions of years.

The ultimate fate of Earth is tied to the Sun. In about 5 billion years, the Sun will swell into a red giant, engulfing the inner planets or making Earth too hot for life. This is a natural, long-term end to our planet’s habitability. But this event is far in the future, so current concerns focus more on human-driven climate change and other nearer-term risks.