Overview
- The study, published in Monthly Notices of the Royal Astronomical Society on May 28–29, 2026, reports six lithium‑rich M‑dwarf stars found in three young star clusters.
- Astronomers say the lithium is unexpected because red dwarfs normally destroy lithium in their hot interiors soon after forming, so a measurable lithium excess can indicate fresh delivery of lithium‑bearing rocky material into a star.
- Researchers identified the stars using Gaia‑ESO Spectroscopic Survey data from the FLAMES instrument on the VLT and estimate each star accreted roughly 3 to 10 Earth‑masses of rocky material.
- The team tested other causes such as prolonged accretion from disks and magnetic effects and judged them poor fits, but they caution that confirming planetary engulfment will need more spectra, time‑domain follow‑up, and modeling of lithium dilution timescales.
- If confirmed, the finding matters because red dwarfs are the Galaxy’s most common stars and host many Earth‑size planets, so early engulfment could lower the odds that some rocky worlds survive long enough to develop habitable conditions.