The Massive Accreting Black Hole at the Center of the Milky Way*

The Galactic Center is the best established case for a super-massive black hole. Its mass is of the order of 3–4 million solar masses and can be associated with the compact variable radio source Sagittarius A* (SgrA*) and shows powerful flare activity both at X-ray and near-infrared wavelengths. A recent simultaneous detection of such a flare with the VLT and Chandra in both of these spectral bands suggests that they are physically linked and probably originate from the same population of electrons.