How Often Do Stars Consume Nearby Planets? New Findings from Gaia Data
A team of astronomers from the Australian National University in Canberra has illuminated how frequently stars can swallow the planets that orbit them. The research, published in a leading science journal, investigates the fate of planetary systems when their stars undergo dramatic changes.
Earlier work hinted that some distant stars carry unusual elemental signatures. These clues, along with other measurements, suggested that planets may be absorbed by their host stars. Yet the frequency of such events remained uncertain.
In the latest study, researchers leveraged data from the European Space Agency’s Gaia satellite to examine 91 star pairs. In each pair, the stars lie relatively close to one another, separated by less than a million astronomical units. An astronomical unit equals the average distance between the Sun and the Earth, about 150 million kilometers.
Astronomers determine stellar compositions by analyzing the light that stars emit when molecules heat up. Each element leaves a distinctive spectral fingerprint, allowing scientists to read the chemical make-up of distant suns.
The analysis revealed that roughly 8 percent of the stars in these paired systems show signs of having swallowed planets. This conclusion is supported by differences in the chemical signatures between the two stars in each pair.
Experts say the study provides a new way to estimate how common unstable star systems are and how planetary systems evolve in such environments.
Earlier discoveries noted a black hole consuming a nearby star, offering another glimpse into how extreme gravitational forces reshape celestial bodies.