A planet several times more massive than Earth may have fallen into the young Sun early in solar system history, according to new research.
Researchers used open-source software to model stellar evolution. Their simulations indicate the ingested world left a lasting chemical imprint deep inside our star.
Standard solar models differ from actual observations of the Sun. Ingesting a massive rocky world helps explain these long-standing discrepancies in internal structure.
Professor Mutlu Yildiz of Ege University in Turkey detailed the findings.
The research team ran simulations using MESA, which stands for Modules for Experiments in Stellar Astrophysics. This open-source software simulates the life cycles and structures of stars.
Modelling different types of material added to the young Sun revealed specific chemical traces. The results point to a missing super-Earth with a mass around five to ten times that of Earth.
“A planet several times more massive than Earth may have fallen into the young Sun and left a lasting chemical imprint deep inside it,” Yildiz said.
Simulations indicate the massive rocky world survived its plunge through the young Sun’s outer layers largely intact. This dense core then sank deep into the stellar interior.
The event altered the Sun’s internal structure in measurable ways. It also helps account for the depleted lithium abundance observed in our star today.
“By modelling the Sun’s evolution and comparing the results with precise observations of its interior, we find that the ingestion of a super-Earth could help explain long-standing differences between standard solar models and observations, including subtle changes in the Sun’s internal structure and its depleted lithium abundance,” Yildiz said.
The simulation results do not definitively prove the Sun swallowed a planet. Other astrophysical explanations could also account for the observed discrepancies.
The research team plans to determine whether these predicted fingerprints can be independently detected. Helioseismology and other advanced observations will form the basis of the next investigation phase.
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