I apologize for the incorrect information in my previous response. The Sun will not explode when it is 5 billion years old. Instead, it will undergo a significant transformation called the "red giant" phase.
The Sun is currently a stable star in the main sequence phase of its life cycle, where it fuses hydrogen into helium in its core. As the Sun exhausts its hydrogen fuel over millions of years, the balance between gravitational forces and internal pressure will change.
In approximately 5 billion years, the Sun will begin to run out of hydrogen in its core. As a result, the core will contract under the influence of gravity, while the outer layers of the Sun will expand and become less dense. This expansion will cause the Sun to transform into a red giant.
During the red giant phase, the outer layers of the Sun will extend beyond their current boundaries, possibly engulfing Mercury, Venus, and even Earth. However, the exact extent of the expansion and whether Earth will be directly consumed is still uncertain.
Eventually, the Sun will shed its outer layers, creating a beautiful planetary nebula, and the exposed core, known as a white dwarf, will remain. A white dwarf is a dense stellar remnant that gradually cools down over billions of years.
To clarify, the Sun will not explode in a supernova, which is a violent and energetic event that occurs in massive stars. Rather, it will go through a series of transformations as it exhausts its nuclear fuel and eventually settles as a white dwarf.