It is not every day that a cosmic discovery challenges established laws at this point. Researchers observed the Andromeda galaxy, also called M31, one of our closest neighboring. They discovered a very unusual provision of its satellite galaxies there. An unlikely arrangement that it might require to review our current understanding of the universe.
Normally, small satellite galaxies disperse randomly around their host galaxy. However, almost all Andromeda satellites are on one side and point directly to our Milky Way, reports the online media Futurism. According to standard cosmological simulations, the probability of such a alignment is only 0.3%.
Even more surprising, half of these satellites orbit in the same plane, comparable to the way in which the planets of our solar system revolve around the sun. This kind of observation questions the classic vision of a chaotic distribution according to galactic mergers.
In the universe, the formation of galaxies is largely guided by halos of dark matter. These invisible groupings, which would represent 85% of the whole mass of the universe, exercise an immense gravitational force. It is this influence that helps small galaxies to come together and merge to train larger galactic structures.
Anomaly or unknown phenomenon?
Several hypotheses are envisaged in order to explain this extremely rare phenomenon. One of them suggests that many satellite galaxies remain invisible for the moment, thus distorting the perception that we have of their arrangement. Another assumes that Andromède would have recently experienced an important episode of fusion of small galaxies, then disturbing the configuration of his satellites.
Kosuke Jamie Kanehisa, Astronomy Research at the Leibniz Institute of Potdam Astrophysics in Germany and the main author of the study published in the Journal Nature Astronomy, specifies: “M31 is the only system we know that demonstrates such an extreme degree of asymmetry”.
Difficult at this point of knowing why the distribution of galaxies around M31 is also special. Kanehisa considers that it is too early to draw final conclusions. Andromède may not be an exception, but the first of this type we meet.
Other galaxies, more distant and difficult to observable, may have similar configurations. You will understand, we know only one thing is that we don’t know much.
