A survey published this Monday (30) in the scientific journal Nature Astronomy suggests that at least a quarter of the Sun-like stars have planets that orbit them. The discovery could help understand the possible evolutionary path of planetary systems.
The galaxy we live in has many planetary systems, and it was already known that most of them are quite different from our solar system.
But now scientists have discovered that, unlike our Solar System – which has preserved a systematic architecture of planets orbiting the Sun – a significant number of neighboring planetary systems have had a very dynamic past. In at least 25% of them, the central star must have “devoured” some of the planets that orbited it.
The study, conducted by researchers from the University of So Paulo (USP) and centers in Italy, Australia and the United States, observed the chemical composition of more than 100 solar-type stars. binary system A system formed by two twin stars having the same chemical composition. For this, La Silla Observatory Telescope, managed by European Southern Observatory (ESO) and is located in the Atacama Desert in Chile.
To the scientists’ surprise, some of the binary systems analyzed did not have the same chemical composition as sister stars, as one of them had a greater Lithium and Iron, an element abundant in rocky planets.
Timelapse shows the sky from the La Silla Observatory in Chile
The conclusion, according to Jorge Melendez, a professor in the USP Department of Astronomy and one of the authors, is that stars rich in these elements had some planets dissolved in their systems in their outer region. Therefore . nickname of “Cannibal Star”.
“The unusually high abundance of this chemical element in a star [lítio e ferro] This could indicate that planetary material was swallowed by it,” Melendez says.
The publication states that the chemically inhomogeneous binary stars discovered by the study “represent one of the most contradictory examples in stellar astrophysics and a source of tension between theory and observations.” Furthermore, it is still unclear what causes the difference in the composition of these twin stars.
La Silla Observatory in Chile’s Atacama Desert, a 3.6-meter telescope from the European Southern Observatory (ESO). — Photo: Yuri Beletsky (LCO)/ESO
“It is still unclear whether the chemical abundance variation is a result of disparities in proto-stellar gas clouds. [da formação estrelar] or are due to planetary collision events (…) The first scenario undermines the common belief that the chemical composition of stars provides fossil information on the environment in which they formed, while the second scenario sheds light on possible evolutionary pathways. puts the planetary system, ”the publication states.
However, scientists say that there is strong evidence that the planets are surrounded by the central star of the system.