Published in "Observational Evidence for the Black Holes in the Universe", Conference held in Calcutta, January 11-17th, 1999., p. 157

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Abstract. I review the status of observational determinations of central masses in nearby galactic nuclei. Results from a variety of techniques are summarized, including ground-based and space-based optical spectroscopy, radio VLBI measurements of luminous water vapor masers, and variability monitoring studies of active galactic nuclei. I will also discuss recent X-ray observations that indicate relativistic motions arising from the accretion disks of active nuclei. The existing evidence suggests that supermassive black holes are an integral component of galactic structure, at least in elliptical and bulge-dominated galaxies. The black hole mass appears to be correlated with the mass of the spheroidal component of the host galaxy. This finding may have important implications for many astrophysical issues.

Table of Contents

• MOTIVATION
• EARLY CLUES FROM PHOTOMETRY
• METHODS BASED ON STELLAR KINEMATICS
• METHODS BASED ON GAS KINEMATICS
• Optical Emission Lines
• Radio Spectroscopy of Water Masers
• Determining Central Masses of Active Galactic Nuclei
• INDIRECT, BUT TANTALIZING EVIDENCE
• ARE THE MASSIVE DARK OBJECTS REALLY BLACK HOLES?
• THE BLACK-HOLE MASS/BULGE MASS RELATION
• ARE SUPERMASSIVE BLACK HOLES UBIQUITOUS?
• SOME IMPLICATIONS AND FUTURE DIRECTIONS
• REFERENCES