Counter Rotating Cores Formed by Minor
Mergers
A
number of elliptical galaxies have been found
to contain counter rotating cores. This means that the inner part of the
galaxy is rotating in the opposite sense to the rest of the galaxy. One
method of formation is where dynamical friction causes a small compact
satellite galaxy to spiral into the center of a much larger galaxy as seen
below. If the satellite is initially on a retrograde orbit with respect
to the rotation of the larger galaxy it may form the counter rotating core.
The light blue particles are
from the large (primary) galaxy and the red are from the small (satellite)
galaxy. The three plots show the satellites track from three different
views.
