The age of the Earth, estimated to be around 4.5 billion years, is based on scientific evidence and geological dating methods. However, the lifespan of the Earth and the eventual outcome of its existence depend on various factors and processes.
One significant event that may occur in about 4.5 billion years is the predicted increase in luminosity of our Sun as it enters the red giant phase of its evolution. During this phase, the Sun will expand in size and become much hotter, potentially causing significant changes on Earth. It is projected that the increased solar luminosity will lead to the loss of the Earth's atmosphere and the eventual destruction of the planet's surface, rendering it inhospitable for life as we know it.
However, it's important to note that the exact timeline and outcome are subject to scientific modeling and predictions, which may change as our understanding of stellar evolution advances. Additionally, other factors such as potential asteroid impacts or interactions with other celestial bodies could impact the Earth's future.
Nonetheless, in terms of the long-term future of the Earth, the ultimate fate of our planet will likely depend on processes like stellar evolution, gravitational interactions within the solar system, and the overall lifespan of the Sun.