Giant stellar arcs in the Large Magellanic Cloud: a possible link with
  past activity of the Milky Way nucleus
  The origin of the giant stellar arcs in the LMC remains a controversial
issue, discussed since 1966. No other stellar arc is so perfect a segment of a
circle, moreover, there is another similar arc nearby. Many hypotheses were
advanced to explain these arcs, and all but one of these were disproved. It was
proposed in 2004 that origin of these arcs was due to the bow shock from the
jet, which is intermittently fired by the Milky Way nucleus and during the last
episode of its activity the jet was pointed to the LMC. Quite recently evidence
for such a jet has really appeared. We suppose it was once energetic enough to
trigger star formation in the LMC, and if the jet opening angle was about
2{\deg}, it could push out HI gas from the region of about 2 kpc in size,
forming a cavity LMC4, but also squeezed two dense clouds, which occurred in
the same area, causing the formation of stars along their surfaces facing the
core of the MW. In result, spherical segments of the stellar shells might
arise, visible now as the arcs of Quadrant and Sextant, the apices of which
point to the center of the MW. This orientation of both arcs can be the key to
unlocking their origin. Here we give data which confirm the above hypothesis,
amongst which are radial velocities of stars inside and outside the larger one
of the LMC arcs. The probability is low that a jet from an AGN points to a
nearby galaxy and triggers star formation there, but a few other examples are
now known or suspected.
