The main clue is a sharply elevated lithium content in the star’s atmosphere. Planets are usually richer in lithium than stars. When a star engulfs a planet, this element remains in its outer layers, creating a characteristic chemical “fingerprint.”
The star TOI-5882 has not yet entered the red giant stage, so simple expansion cannot easily explain the engulfment. Astronomers suggest that a massive brown dwarf, which also orbits the star, may have “helped” the planet. It could have disrupted the planet’s orbit and sent it to its inevitable demise.
This discovery is important not only in itself. It helps to understand how planetary systems evolve and why some stars exhibit anomalous chemical compositions. In the future, our Solar System faces a similar fate: in several billion years, the Sun, having become a red giant, will engulf Mercury, Venus, and possibly Earth.
Author: Maksim Aleksandrovich Erdyakov.