  We report on the nature of prominent sources of light and shadow in the
Galactic Center. With respect to the Bremsstrahlung X-ray emission of the hot
plasma in that region the Galactic Center casts a 'shadow'. The 'shadow' is
caused by the Circum Nuclear Disk that surrounds SgrA* at a distance of about 1
to 2 parsec. This detection allows us to do a detailed investigation of the
physical properties of the surroundings of the super massive black hole.
Further in, the cluster of high velocity stars orbiting the central super
massive black hole SgrA* represents an ideal probe for the gravitational
potential and the degree of relativity that one can attribute to this area.
Recently, three of the closest stars (S2, S38, and S55/S0-102) have been used
to conduct these investigations. In addition to the black hole mass and
distance a relativistic parameter defined as ${\Upsilon}=r_s/r_p$ could be
derived for star S2. The quantity $r_s$ is the Schwarzschild radius and $r_p$
is the pericenter distance of the orbiting star. Here, in this publication, we
highlight the robustness and significance of this result. If one aims at
investigating stronger relativistic effects one needs to get closer to SgrA*.
Here, one can use the emission of plasma blobs that orbit SgrA*. This
information can be obtained by modeling lightcurves of bright X-ray flares.
Finally, we comment on the shadow of the SgrA* black hole expected due to light
bending and boosting in its vicinity.
