Earth May Escape Fiery Doom: New Study Suggests Wider Orbit Could Save Planet
A study published in Astronomy & Astrophysics on Friday suggests that Earth might not be engulfed by the Sun when it expands into a red giant in about five billion years. The research, led by Mats Esseldeurs of the University of Leuven, Belgium, indicates that lower-than-expected tidal dissipation within the dying Sun could allow Earth to move to a wider orbit, escaping destruction.
Background
As the Sun exhausts its hydrogen core, it will expand into a red giant and later an AGB star. This expansion creates tidal forces that would typically pull Earth inward. However, the Sun will also lose mass via stellar wind, pushing Earth outward. Previous models favored Earth's engulfment, but improved tidal modeling suggests mass loss may dominate.
Key Findings
- The study analyzed tidal dissipation in giant stars, finding it lower than previously estimated.
- Earth's fate depends on the balance between tidal forces and solar mass loss.
- Under the new model, Earth and Mars may avoid being engulfed, while Mercury and Venus will be consumed.
- The Sun will eventually become a white dwarf.
Expert Statements
"Earth's fate depends on a delicate balance between these two effects."
— Mats Esseldeurs, Lead Researcher
Co-author Stephane Mathis noted that "a better understanding of tidal physics and mass loss constraints allow us to say that Earth could move away from the Sun."
The study focused on the star L2 Puppis, described as the Sun's "old cousin," to estimate mass loss.
Note: All life on Earth will have ended long before these events occur.