The Galactic Center
Left: Highest resolution (0.0002") image ever obtained of the Galactic Center via VLBA observations at 3mm. The slight extension in the east-west direction shows that emission is resolved at 20 Schwarzschild radii from the central supermassive black hole.
The presence of the supermassive black hole SgrA* in the Galactic Center has driven some of the studies carried out at the ASIAA. One long term project has been the attempt to resolve the radio continuum emission from SgrA* using VLBI techniques. The latest VLBA results, reported in Nature, show a radio image of SgrA* at 3mm. This work demonstrates that an object of approximately four million solar masses is confined within just 1 AU. It provides the strongest evidence that SgrA* is a supermassive black hole.