The Earth’s outer core is estimated to be around 2.5 to 3 billion years old. This estimation is based on the age of the Earth’s formation and the geological processes that have occurred over billions of years.
The Earth itself formed about 4.5 billion years ago from the accumulation of dust and gas in the solar system. During its early history, the planet was mostly molten due to high temperatures from collisions and radioactive decay. As the Earth cooled, heavier elements, like iron and nickel, sank towards the center, forming the outer and inner core.
The outer core is in a liquid state and is composed primarily of molten iron and some nickel, along with lighter elements. This layer plays a crucial role in the generation of Earth’s magnetic field through the dynamo effect, which is driven by the movement of the molten metal within it.
In summary, while we can estimate the age of the outer core based on the formation of the Earth, ongoing research continues to refine our understanding of its characteristics and history.