The Sun is approximately 4.6 billion years old, according to modern scientific estimates.
This estimate is based on the study of isotopes and the age of the oldest meteorites found in our solar system, which provide a window into the time when the Sun and the planets formed. Scientists use radiometric dating techniques to analyze these meteorites, leading to the conclusion that our solar system developed around 4.6 billion years ago, with the Sun being at the center of this cosmic process.
The age of the Sun helps astronomers understand not just its lifecycle but also the history of our solar system. The Sun has enough fuel to continue shining for several billion more years before it exhausts its nuclear fuel and evolves into a red giant and eventually a white dwarf.