In 1 billion years, Earth will no longer be able to support surface water. The visualization does not consider the shifting of Earth’s tectonic plates over that time period, but it provides insight into the potential future landscape of our planet. Credit: NASA’s Scientific Visualization Studio
When considering the remaining lifespan of life on Earth, it is inevitable to ponder the eventual fate of the celestial body that nurtures us — the Sun. It will be approximately 5 billion years before the Sun depletes its fuel and expands into a red giant, posing a significant threat to engulf and obliterate our home planet. At first glance, this timeframe may seem ample, doesn’t it?
However, the reality is that Earth’s clock is ticking much faster than anticipated. Despite the Sun’s current abundance of nuclear fuel to sustain itself, it is gradually undergoing changes, following the natural course of stellar evolution. The Sun’s core facilitates nuclear fusion reactions, converting hydrogen atoms into helium, with the resultant helium accumulating as ashes due to the lack of an exit route. Consequently, the core increases in density, elevating pressure levels and causing the Sun’s nuclear furnace to intensify.
Consequently, the Sun grows progressively brighter over time, currently experiencing an approximate 10 percent increase in luminosity every billion years. In roughly another billion years, this heightened energy output will inevitably lead to a rise in planetary temperatures, triggering the evaporation and eventual disappearance of Earth’s oceans. The habitable zone within our solar system — the region where liquid water can viably exist on a planet’s surface — will have shifted outward, leaving Earth devoid of this life-sustaining element.
Hence, it emerges that the narrative of life on Earth has already reached 80 percent completion, transitioning towards its final chapter.