Possible evidence from the flaring activity of Sgr A* for a star at a
  distance of ~3.3 Schwarzscild radii from the blackhole
  The frequent flaring events in the X-ray and the NIR radiation of Sgr A* seem
not to be periodic in time. However, statistical regularities, here termed
"modulations by a pacemaker", are found in the recorded arrival times of both
types of events. The characteristic time of the X-ray pacemaker is 149 min and
that of the NIR pacemaker is 40 min. Their reality as derived from observed
data can be accepted at larger than 4.6{\sigma} and 3.8{\sigma} levels of
statistical confidence, respectively. These results can be interpreted as
evidence for a star that revolves around the BH of Sgr A* in a slightly
elliptical precessing orbit, at a distance of 3-3.5 Schwarzschild radii of the
BH. The period of the X-ray pacemaker, which is not a periodicity of the flare
occurrences themselves, is the epicyclic period of the star orbital motion.
This is the time interval between 2 successive passages of the star through the
peri-center of its orbit. The NIR pacemaker period is the sidereal binary
period of the star revolution. The origin of the X-ray flares is in episodes of
intense mass loss from the star that occur preferably near the pericenter phase
of the binary revolution. The NIR flares originate or are triggered by
processes that are internal to the star. The radiation emitted in the direction
of Earth is slightly modulated by the changing aspect ratio of the two
components of the BH\star binary to the line of sight from Earth at the
sidereal binary frequency.
