Loops are spectacular structures often seen around nearby galaxies.
Many such examples can be seen in the papers by Martinez-Delgado and his
collaborators (2010AJ....140..962M). Till recently it was widely believed
that they are due to small satellites falling in their parent galaxy. Yet
lately we showed that they can also result naturally from a major merger of
two gas-rich progenitor galaxies (26A...538A.121W).

Click here, here and there to follow the evolution of the gaseous component and here for the
stellar component (i.e. the stars born during the interaction and merging)

The initial conditions for this simulation are analogous to those of the
simulations described and analysed in
26A...538A.121W.