The mystery of the universe…a three-dimensional map showing the movement of the stars in spherical clusters

A team of researchers at the National Institute of Astrophysics (INAF) has succeeded in presenting the first three-dimensional view of the formation and evolution of globular star clusters, which are one of the oldest star clusters. in the world. universe.

The study was published in the journal “Astronomy and Astrophysics“Astronomy & astronomy provides an unprecedented understanding of the motion of stars within our galaxy’s 16 globular star clusters, helping to unravel some of the most complex mysteries of those old records have.

Globular clusters are among the oldest star systems in the universe, with their age reaching around 13 billion years, meaning that they date back to the beginning of the creation of the universe.

Due to their high density and long lifetime, these clusters represent natural laboratories for studying the chemical and spatial evolution of galaxies.

Although the study of these clusters began more than 100 years ago, recent findings reveal major gaps in our understanding of them, especially with the discovery that global clusters are not just random clusters, but that they include more than one type of star. .

How were globular clusters estimated?

The study was based on data from the European Space Agency’s Gaia Space Observatory and data from the European Large Telescope, and used three-dimensional analyzes to measure the velocities and directions of motion of stars within the clusters, and to to determine the transit differences between stars. various chemical substances.

Lead author of the study, Emanuele D’Alessandro, said: Understanding the physical processes that led to the formation of globular clusters and their early evolution has been one of the most controversial questions in astrophysics over the past 25 years. ‘ gone.

D’Alessandro pointed out that the results show for the first time that globular clusters were formed over several cycles of star formation, which changes our traditional view of this type of stellar system, meaning that the stars in these clusters were all created at the same time, but appeared in different stages and times.

The researchers found that there are dynamic differences between stars with different chemical compositions in some stars there are unusual amounts of light elements such as helium, oxygen, sodium, and nitrogen.

For his part, the co-author of the study Mario Cadelano said that despite the large number of ideas and theoretical models, the mechanisms that control the formation of these stars with a combination of chemicals.

The study said that stars with different chemical compositions are distributed in different ways within the clusters, as stars with irregular compositions are clustered more towards the center of the cluster, which is ‘ indicate that they were first created and then modified to gradually move to the periphery.

Stars with irregular compositions contain unusual proportions of light chemical elements such as helium, oxygen, sodium and nitrogen.

In globular star clusters, these stars are distinguished from “normal” stars that contain current ratios of these elements, which are generally similar to those found in other stars in the galaxy.

The lead author of the study noted that these results are consistent with theories of the long-term kinetic evolution of stellar systems, and confirm the idea that globular clusters were formed over several star formation cycles.

The researchers noted that this new understanding contributes to solving complex puzzles about the origin of these ancient systems. an important piece to the puzzle of the evolution of the universe and galaxies.