200 pc
5 pc
Sagittarius A* - Sgr A*
Slide 28
Infrared images of stars in the Galactic Center over 8 years.
The “+” is the radio source Sgr A*
Conclusion: Must be over one million solar masses within less than 1/5 of a light year!
Supermassive Black Hole!
Event Horizon < 0.05 AU!
Probably in the centers of all spiral galaxies.
Copyright Eckart & Genzel