Data from the Gaia space mission suggests that the nearest cluster of stars to the Solar System is being shattered by dark matter, as “normal” processes do not explain a particular occurrence – supposedly generated by the gravitational field of something we cannot yet see. The damage, according to the researchers ahead of the analysis, extends to anything within reach of the unknown elements.
The “arm wrestling” between internal and external forces to which a concentration of stars is subjected is part of the daily life of the groups, which end up separated into true rivers of stars. However, mapping the phenomena involves overcoming complicated obstacles, such as the detailed measurement of the distances of what they compose, hampered by several factors.
In this sense, terrestrial equipment works incessantly in the provision of characteristics in three dimensions, thus offering the largest possible number of data, such as the position of objects and their speeds. Gaia’s do that.
Thanks to them, several unknown “currents” of stars, including “tails” that started to detach themselves from the Hyads (cluster in question), under the effect of the tide of forces acting on the bodies, came to the attention of the scientific community in 2019.
At the time, the finding caught the attention of astronomer Tereza Jerabkova and her colleagues at the European Space Agency and the European Southern Observatory, and all focused on expanding the parameters raised to previous detections, lacking such information.
With this, the surprise, published in the magazine Astronomy & Astrophysics: hundreds of stars associated with the set were thousands of light years away, even though the central region is only 60 light years in diameter.
According to Jerabkova and his team, despite the normal presence of tails in similar formations, simulations about the cluster suggested that more stars should be there.
Intrigued, the scientists decided to run more models to understand what could have lost the stars, and the results suggested that this would be the result of the cluster’s interaction with a massive object, which would have about 10 million times the mass of the Sun – still invisible to us.
As a curiosity, from the identification of gravitational effects, researchers estimate that 80% of all the matter in the Universe is that dark matter, an essential part of the formation of galaxies and, in turn, also gathered in large clusters.
For example, even the Milky Way, with its 1.9 million light years in diameter, would have ‘dark halos’ extended around it – containing, in themselves, their own sets, mere vagrants.
“The way we see the Milky Way has completely changed”, celebrates Tereza – indicating that future research may focus on these star interruptions in the tails of clusters, after all, they would offer important clues about the subject and, in addition, they would reveal, who knows, which, in fact, causes them.
“We will be able to map structures in the best ways seen so far”, concludes the astronomer.