November 10, 2024: Astronomers have discovered an Earth-sized, rocky planet orbiting a white dwarf star in the constellation Sagittarius, roughly 4,000 light-years away. This find suggests that Earth, or at least humanity, might have hope for survival even as our sun enters its final, red-giant phase. The rocky planet, similar in mass to Earth, sits in an orbit around a dead star—signifying what could eventually become of our solar system.
This discovery may imply that Earth, or life itself, could avoid destruction by the expanding sun. As our sun loses mass and expands, planets may be pushed outward, potentially allowing it to escape. However, even if Earth survives this phase, it may not remain habitable; in about a billion years, rising temperatures will likely evaporate Earth’s oceans due to a runaway greenhouse effect.
In the far future, the habitable zone in our solar system will shift toward Jupiter and Saturn’s orbits, making their icy moons, like Europa and Callisto, possible refuges for humanity.
Jessica Lu from UC Berkeley commented, “Earth may avoid being swallowed by the sun when it becomes a red giant, but whether life could survive such changes is uncertain.” Lead researcher Keming Zhang suggested that when Earth becomes inhospitable, humanity may need to look to these distant moons as potential new homes.
