Mass, Distance, Spin, Charge, and Orientation of the super massive black hole SgrA*

SgrA* at the center of the Milky Way is the supermassive black hole that is most suited for a determination of its fundamental properties. Here, we summarize the most recent results on mass and distance, spin, and charge, and put them into the context of representative revious measurements. The data which these results are based upon have mostly been taken with large infrared single telescopes, the ESO VLTI infrastructure combined with the GRAVITY interferometer, as well as the X-ray imaging using Chandra. One finds: R_SgrA*= 8.12+-0.03 kpc and M_SgrA*= (4.10+-0.03) x 10^6 solar masses, corresponding to relative uncertainties in these quantities of about 0.4% and 0.7%. Spin values above 0.5 are suggested but the model dependent determination is not yet very conclusive. Models suggest that the spin vector is orientated towards the East and inclined towards the observer at an appreciable angle. An observational upper limit of Q_SgrA* <= 3 x 10^8 C can be given for the charge.