We present the first HST long-slit spectrum of a gaseous disk around a candidate super-massive black-hole. The results of this study on the kinematics of the gaseous disk in M87 are a considerable improvement in both spatial resolution and accuracy over previous observations and requires a projected mass of MBH(sin i)2 = (2.0 ± 0.5)×109M⊙ (MBH = 3.2×109M⊙ for a disk inclination i = 52◦) concentrated within a sphere whose radius is less than 0.′′05 (3.5 pc) to explain the observed rotation curve. The kinematics of the ionized gas is well described by a thin disk in keplerian motion. A lower limit to the mass-to-light ratio of this region is M/LV ≃110, significantly strengthening the claim that this mass is due to the presence of a central black-hole in M87. (Refer to PDF file for exact formulas).

Publication Date



Also archived in: arXiv:astro-ph/9706246 v1 24 Jun 1997 Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555 and by STScI grant GO-3594.01-91A.ISSN:1365-2966 Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

Document Type


Department, Program, or Center

School of Physics and Astronomy (COS)


RIT – Main Campus