Produced by: BT Desk
Astronomers discovered KMT-2020-BLG-0414, a rocky planet about twice the size of Earth, located 4,000 light-years away, offering a glimpse into what Earth may look like 8 billion years from now.
This distant planet orbits a white dwarf, the burnt-out remains of a star. In 5 billion years, our own sun is expected to turn into a white dwarf after its red giant phase, according to journal Nature Astronomy.
Before becoming a white dwarf, our sun will expand into a red giant, engulfing Mercury, Venus, and possibly Earth and Mars as it swells to hundreds of times its current size.
The system was first detected in 2020 through gravitational lensing, where the planet’s gravity bent the light of a more distant star, revealing its presence 25,000 light-years away.
Lead author Keming Zhang from UC San Diego suggests Earth will become uninhabitable in roughly a billion years, with oceans vaporizing from a runaway greenhouse effect before the red giant phase.
KMT-2020-BLG-0414 orbits its white dwarf at a distance similar to Earth's orbit around the sun, suggesting a stable path that might resemble Earth’s own future orbit after the sun’s transformation.
The system also contains a brown dwarf, a failed star about 17 times the mass of Jupiter, further enhancing the complexity of this distant solar system.
Zhang speculates that as the sun expands, humanity might migrate to moons like Europa and Enceladus, which could become habitable ocean worlds as the habitable zone shifts outward.