It's currently about halfway through its main sequence lifetime, meaning it has about 5 billion years left.
Here's why:
* Main Sequence: This is the longest and most stable phase in a star's life. During this phase, stars fuse hydrogen into helium in their core, releasing energy that makes them shine.
* Fusion Rate: The rate at which a star fuses hydrogen depends on its mass. Larger stars fuse hydrogen much faster than smaller stars, leading to shorter main sequence lifetimes.
* Sun's Mass: The Sun is a medium-sized star, which means it has a relatively long main sequence lifetime.
After the main sequence, the Sun will evolve into a red giant, then a white dwarf.
