An evolving hot spot orbiting around Sgr A*
  Here we report on recent near-infrared observations of the Sgr A* counterpart associated with the super-massive ~ 4x10^6 M_sun black hole at the Galactic Center. We find that the May 2007 flare shows the highest sub-flare contrast observed until now, as well as evidence for variations in the profile of consecutive sub-flares. We modeled the flare profile variations according to the elongation and change of the shape of a spot due to differential rotation within the accretion disk. 
M. Zamaninasab, A. Eckart, L. Meyer, R. Schoedel, M. Dovciak, V.   Karas, D. Kunneriath, G. Witzel, R. Giessuebel, S. Koenig...