Astronomers analysing data from NASA’s Transiting Exoplanet Survey Satellite (TESS) have found evidence that many planets orbiting stars that are entering the red‑giant phase may not survive. These stars, as they expand and evolve, appear to destroy or engulf planets that are too close.

The research team began with data from nearly 500,000 star systems and identified about 15,000 potential planet signals. Among those, they narrowed their focus to stars entering the red‑giant phase and detected around 130 planets, including about 33 that were previously unknown.

What the study found was striking: the odds of a star in the red‑giant expansion phase hosting a nearby planet drop dramatically. The researchers estimate that such stars have only about a 0.11% chance of hosting a planet, which is about 3 % less than similar stars that are still on the main sequence.

🚀 How Stellar Expansion Threatens Planetary Survival

When a star exhausts the hydrogen in its core, it expands enormously and becomes a red giant. That expansion brings the outer layers much closer to any orbiting planets. As this happens, the planet experiences strong tidal gravitational forces, and its orbit can shrink until the planet spirals into the star.

Researcher Edward Bryant of the University of Warwick explained that while the effect was expected, the degree of planetary loss surprised the team: “We were surprised by how effective red giants are at swallowing their surrounding planets.”

The implications are profound. As our Sun evolves into a red giant in about five billion years, it may engulf Mercury and Venus — and possibly even Earth — scientists warn.

The findings also highlight how planetary systems evolve drastically over time. Planets that seem stable now may face destruction as their host stars age. The results could help scientists model the future of our solar system and others.