For more than a century, the idea that a black hole supermassive inhabits the center of the Milky Way was one of the pillars of the astronomy modern. However, a new study with strong Argentine participation calls this certainty into question and opens the door to an alternative explanation.
The research, led by an international team of astrophysicists linked to CONICET, suggests that the ultra-compact object that dominates the galactic core might not be a black hole «classical», but an extremely dense concentration of dark matter capable of generating similar gravitational effects.
Until now, the scientific consensus indicated that at the center of our Galaxy Sagittarius A* (Sgr A*) is located, located about 26 thousand light years from Solar Systemin the constellation of Sagittarius.
Traditional estimates attribute a mass equivalent to four million times that of the Solenough to control the orbits of stars that move at extreme speeds around them.
The new model proposes that the existence of a black hole with event horizon to explain those phenomena. Instead, a core compact dark matter ultradense could reproduce the same gravitational intensity.
What the new theory is about
The work was published in the journal Monthly Notices of the Royal Astronomical Society and has the participation of researcher Carlos Argüelles, from the Institute of Astrophysics of La Plata (IALP), dependent on the CONICET and the UNLP.
The team also included scientists from the International Center for Relativistic Astrophysics (ICRANet) and the National Institute of Astrophysics (INAF) of Italy, the Relativity and Gravitation Research Group of Colombia and the University of Cologne in Germany.
According to the authors, the most recent data on the movement of the so-called «S stars», which orbit very close to the galactic centerand the profile of the famous «shadow» detected in that region do not rule out this alternative hypothesis.
One of the main challenges was to explain the image obtained by the Event Horizon Telescope, which showed a dark region surrounded by a ring bright.
The new study maintains that a core massive of dark matter could bend the surrounding light in a similar way, generating a «shadow» almost indistinguishable from that attributed to a black hole.
The computational models developed by the team also managed to reproduce with high precision the star orbits closest to galactic center and the behavior of other objects in that extreme zone.
What is dark matter and why this debate is just starting
The dark matter It is one of the greatest enigmas of contemporary physics. It does not emit light or detectable radiation, but its existence is deduced from the gravitational influence it exerts. It is estimated that it constitutes around 85% of the total mass of the universe.
If he core of the Milky Way dominated by such a structure, the impact would be profound: it would force us to rethink the current understanding of galactic nuclei and the role of dark matter in the architecture of the cosmos.
As with any disruptive hypothesis, the debate is open. New observations and high-resolution measurements will be key to confirm or refute the model.
Meanwhile, the proposal places the Argentine science at the center of an international discussion that could redefine one of the most enigmatic points of the universe known: what is, really, in the heart of our Galaxy.
