A new peer-reviewed study, published June 19, 2026, in the journal Astronomy & Astrophysics, suggests Earth may survive the sun's expansion into a red giant. Astronomers used updated stellar evolution models and observations of the star L2 Puppis to reassess Earth's fate.

As the sun expands, increased tidal forces will pull Earth toward the star. However, the sun will also lose its outer layers through stellar wind, which will cause its gravitational grip to weaken. Mats Esseldeurs, a doctoral candidate at KU Leuven's Institute of Astronomy and first author of the study, explained, "The fate of Earth depends on a delicate balance between these two effects." Esseldeurs stated that "If tidal interactions dominate, Earth is engulfed," adding, "If mass loss dominates, Earth escapes to a wider orbit." The researchers performed gravitational calculations based on the internal structure and dynamics of evolved stars and modeled the orbital evolution of the inner solar system and the sun's lifespan.

Based on their observations of L2 Puppis' mass loss and the stellar evolution models, researchers projected that Earth will survive by shifting to just outside the expanding sun's radius. Simulations indicate that Mercury and Venus will be engulfed by the sun.

The sun is expected to have a 10 billion-year life as a yellow dwarf star. In approximately 5 billion years, it will run out of hydrogen to fuse in its core. Following this, the sun will begin fusing hydrogen in its shell and expand into a red giant star. The sun will eventually die as a white dwarf.

Esseldeurs noted that "The largest uncertainty no longer comes from the tidal calculations, but from how much mass the future sun will lose." He said that while observations of sun-like giant stars currently point towards Earth's survival, "we need better observations before we can be certain."

Intact worlds have been discovered around white dwarfs, with some white dwarf systems containing rocky remnants of destroyed planets. The star L2 Puppis is located 200 light-years away in the constellation Puppis. Previous estimates suggest L2 Puppis may be losing up to one-millionth of a solar mass per year, and it is expelling a dusty disk thought to harbor a planet 12 to 16 times the mass of Jupiter. The European Space Agency's PLATO mission, a space telescope scheduled to launch next year, aims to search for Earth-like planets around sun-like stars.

Why It Matters

This study provides an updated outlook on Earth's long-term habitability relative to the sun's life cycle. Previous scientific models have indicated that Earth would be consumed when the sun expands into a red giant. The new research, incorporating detailed observations of a star similar to the sun in a later stage of its life, suggests a different potential outcome. Understanding the processes that determine planetary survival in such scenarios contributes to the broader study of planetary evolution and the potential for life in other star systems.