  We have analysed the light curve of the two brightest X-ray flares from the
Galactic Center black hole, one flare observed by XMM-Newton on October 3, 2002
(Porquet et al. 2003), and the other flare observed by Chandra on October 26,
2000 (Baganoff et al. 2001). The power density spectra show five distinct peaks
at periods of ~ 100 s, 219 s, 700 s, 1150 s, and 2250 s common to both
observations within their estimated measurement uncertainties. The power
density spectrum of the recently reported infrared flare of June 16, 2003
(Genzel et al. 2003) shows distinct peaks at two, if not three, periods
(including the 1008 +/- 120 s infrared period), which are consistent with the
X-ray periods. The remaining two periods could not be covered by the infrared
measurements. Each period can be identified with one of the characteristic
gravitational cyclic modes associated with accretion disks, i.e. either
Lense-Thirring precession, Kepler orbital motion and the vertical and radial
epicyclic oscillation modes, in such a way that a consistent value for the
black hole mass of M_BH = 2.72^{+0.12}_{-0.19} x 10^6 M_odot and the angular
momentum $a$ = 0.9939^{+0.0026}_{-0.0074} is obtained. The available data on
M_BH derived from studies of the orbital motion of the S2 (S0-2) star (Schoedel
et al. 2002, Ghez et al. 2003) agree with our findings. Finally we discuss some
implications of the fairly high value for the angular momentum.
