This age is determined by various methods, including:

* Radiometric dating of meteorites: These are remnants of the early solar system and provide the most accurate age estimates.

* Dating of lunar samples: Analysis of rocks brought back from the Moon by Apollo missions also supports the age of the solar system.

* Dating of the oldest Earth rocks: While Earth's oldest rocks have been recycled over time, the oldest known samples are around 4 billion years old, consistent with the age of the solar system.

So, while the exact age might vary slightly depending on the method used, 4.54 billion years is the generally accepted age of the solar system.