Inventory of the Galactic Center 

How do we study the center of the Galaxy? At the distance of the Galactic Center, 1" is about 0.05 parsecs.

What do we see?

A rising density of stars towards the center: ρ(r)\rho(r) ~ r-2 from 1 parsec to 0.1 parsec. Stars are very close together, so close interactions are common.

Lots of non-thermal synchrotron radio emission showing ionized gas and magnetic fields:

The brightest radio source is called Sagittarius A (Sgr A). Sgr A is not a single object, but a complex region at the center of the Galaxy:

VLA radio image (Farhad-Zadeh & Morris)