A tale of two tails: insights from simulations into the formation of the
  peculiar dwarf galaxy NGC 1427A
  We present a scenario for the formation and the morphology of the
arrow-shaped dwarf irregular galaxy NGC 1427A in the Fornax Cluster. This
galaxy shows intriguing stellar and gaseous tails pointing in different
directions for which alternative but not conclusive formation scenarios have
been proposed in the literature. We performed N-body/SPH simulations of dwarf
galaxies falling into a model of the Fornax cluster, exhibiting a
jellyfish-like appearance while undergoing ram-pressure stripping. We noted
that some of our models show interesting tail morphologies similar to that of
NGC 1427A. In this way, the peculiar NGC 1427A structure can be studied using
models whose stellar and neutral gas photometry and kinematics are in good
agreement with the observed ones, without the need of invoking an interaction
with a nearby galaxy. Thanks to the tails, we can identify the requirements for
a galaxy to expose such a structure and assess the possible position and
velocity of the galaxy in the cluster. This puts constraints on the orbit of
the galaxy, its position in the cluster and the time since its pericentre
passage. From the statistics of identified snapshots following our modelling,
we found that the most likely position of the galaxy is around 200 kpc in front
of the cluster centre, travelling towards the cluster with a velocity angle
with respect to the line-of-sight direction of around 50 deg. This analysis can
be useful in future observations of similar galaxies in clusters to
characterise their position and velocity in the cluster and their formation.
