A recent study of 91 or more twin star systems has discovered that their respective planets, sharing similar sizes and chemical makeups, show indications of consuming another planet. Researchers suggest that this cosmic event might have taken place following the displacement of the planet from its stable orbit due to various potential causes.
Over the course of approximately 4.5 billion years, Earth and its fellow planets, as members of a sun-centered planetary system, have maintained stability. However, recent findings indicate that not all planetary systems enjoy such fortune.
Researchers have examined pairs of stars that were born within the same interstellar cloud of gas and dust, sharing a similar chemical composition and mass. These stars, referred to as “twins,” are not gravitationally bound binaries but rather move in harmony within the Milky Way galaxy.
When a star consumes a planet, its elemental makeup transforms as it absorbs the components of the destroyed world. Scientists sought out stars that displayed noticeable differences from their counterparts, exhibiting elevated levels of specific elements such as iron, nickel, or titanium. These heightened concentrations often signify the presence of rocky planet remnants, in contrast to other elements.
Astronomer Fan Liu from Monash University in Australia, the lead author of a study published in Nature, commented, “It’s the disparities in elemental abundance between two stars in a shared birth system.”
In 7 of the star pairs, one star displayed indications of a planet being consumed. Potential causes for a planet plunging towards its host star may involve orbital disruptions due to the presence of a bigger planet or another star coming too close, which can destabilize the entire planetary system, according to the researchers.
Astrophysicist and study co-author Yuan-Sen Ting from the Australian National University and Ohio State University commented, “This discovery truly highlights our fortunate location within the universe. We often take for granted the stability of a planetary system, like our solar system, but it is not a guaranteed occurrence.”
