5 to 7 Billion Years from Now: The Sun Becomes a Red Giant
- The Sun will exhaust its hydrogen fuel and begin burning helium, causing it to expand into a red giant approximately 256 times its current size.
- This expansion will engulf the inner solar system, swallowing Mercury and Venus.
5 Million Years Later: Earth’s Ecosystem Begins to Collapse
- The Sun’s expansion will cause extreme heat, depleting Earth’s carbon dioxide reserves.
- Without carbon dioxide, plants will die, halting oxygen production.
- The death of plants will lead to the extinction of mammals, birds, and other oxygen-dependent creatures.
- As temperatures rise further, even insects will vanish, leaving behind only microbial life.
Final Survivors: Tardigrades
- Tardigrades, known for their resilience, will be the last organisms to survive on Earth.
- They can withstand extreme heat and radiation but will eventually succumb to the Sun’s relentless expansion.
Extreme Heat and Loss of Atmosphere
- Earth’s surface temperature will exceed 2,400 K (2,130°C or 3,860°F).
- The atmosphere will be stripped away, leaving the surface barren and covered with metal and metal oxides.
- Intense radiation will make Earth uninhabitable, and all remaining life will perish.
Tectonic Plates Stop Moving
- With the evaporation of all water, Earth’s tectonic activity will cease.
- The surface will transform into a vast lava ocean.
7.6 Billion Years from Now: Earth and Moon Engulfed by the Sun
- The Sun, as a red giant, will engulf Earth and the Moon, reducing them to cosmic debris.
- The Kuiper Belt, far beyond Neptune, will become the new habitable zone due to the Sun’s expansion.
- Triton (a moon of Neptune) and Eris (a dwarf planet) could host future human colonies, thanks to the presence of liquid water.
1 Quadrillion Years Later: The Sun Becomes a Black Dwarf
- After its red giant phase, the Sun will shed its outer layers and become a white dwarf, a dense, dying star.
- Over time, the white dwarf will cool and transform into a black dwarf, a cold, dark remnant of its former self.
Future Habitats Beyond Earth
- As the Sun’s habitable zone moves outward, humanity may establish colonies on:
- Neptune’s moon Triton, rich in volatile ices.
- Eris, where liquid water could emerge due to warming from the Sun’s red giant phase.
- These icy worlds, once frozen, will provide the conditions necessary for sustaining life.
The Legacy of Earth
Though Earth will meet its end, its legacy could live on in human migration to the outer solar system, continuing the story of life in new and distant worlds.
