Observed the galaxy wagging its tail, thanks to a long tail of about two and a half million light years, twice as long as expected.
It is located in the center of the Abell 1775 cluster, nearly a billion light-years away from Earth.
It is described in the journal Astronomy & Astrophysics by an international research in which Italy participated with the National Institute of Astrophysics (Inaf)
The research is based on images collected by NASA's Chandra X-ray satellite and the European radio telescope Lofar (Low frequency array), consisting of thousands of antennas distributed in the Netherlands and other European countries, managed by the Dutch Astron institute together with a international consortium of which INAF is also a member.
The galaxy has a particular shape, which experts refer to as 'head-tail'. For the authors of the study, "it is one of the fastest in the cluster and hosts an active black hole at its center, which swallows the surrounding matter at a sustained rate and, at the same time, expels a part of it in the form of jets strong radio emission. These jets - explain the astronomers - due to the high speed of the galaxy and the pressure exerted on it by the surrounding hot gas, bend near the black hole, forming a tail, that is a very long trail of electrons and magnetic fields ”.
Thanks to the new observations, astronomers have realized that the tail region arises near a point where the trail of electrons and magnetic fields seems to break. "It is here - conclude the scholars - that the tail slightly changes direction, as if the galaxy were wagging its tail".
