Overview
- A peer‑reviewed Letter published June 19, 2026 uses revised tidal‑dissipation models and data from L2 Puppis to show scenarios in which Earth’s orbit widens enough to avoid direct engulfment by the Sun.
- The study finds weaker tidal braking inside giant stars than earlier work assumed, which reduces the inward pull that would otherwise draw nearby planets into the expanding star.
- Mass loss from the Sun during its red‑giant and asymptotic giant branch phases can weaken solar gravity and push planetary orbits outward, and the study shows that this effect can outweigh tides in some plausible cases.
- Simulations consistently predict Mercury and Venus will be swallowed, Mars probably survives, and Earth’s physical survival would not preserve surface habitability because heat and wind will strip oceans and atmosphere long before engulfment.
- Researchers say the dominant remaining uncertainty is the Sun’s mass‑loss rate and call for better observations of evolved sunlike stars and forthcoming missions such as ESA’s PLATO to narrow the outcome.