Astronomy Zurich researchers explain the formation of cosmic celestial bodies
A Zurich research team has solved the mystery of the origin of cosmic nomads. Contrary to what was assumed, so-called "objects with planetary mass" are formed in a different process than stars and planets, as the University of Zurich announced on Thursday.
27.02.2025, 10:16
SDA
Planetary-mass objects, or PMOs for short, are as large as planets, but do not orbit around a star like planets, instead drifting freely through space.
Such PMOs have been sighted in large numbers in young star clusters such as the Trapezium cluster in the constellation Orion. However, according to the University of Zurich (UZH), their origin was previously a mystery. Theories assumed that they could be failed stars or planets ejected from their solar system.
However, in a study published in the journal "Science Advances", the researchers showed that PMOs are formed differently from planets and stars.
A third class of objects
"PMOs could represent a third class of objects that are not formed from the raw material of star-forming clouds or by planet formation processes, but from the gravitational chaos of disk collisions," study leader Lucio Meyer from UZH was quoted as saying in the press release.
Specifically, the research team has shown that the cosmic nomads arise from violent interactions of disks around young stars. These interactions occur when two such disks approach each other. In the process, streams of matter are pulled out of the outer areas of the disks and these condense to form independent celestial bodies. In contrast to ejected planets, however, they move synchronously with the stars of their host cluster.
