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The nuclear spectrum of M87 covering the Ly_a-H_a wavelength range was obtained with the HST Faint Object Spectrograph (FOS) trough a 0.21 arcsec aperture. Contrary to some previous claims, a single power law (F(nu)~nu^(-a)) can not reproduce the observed continuum shape and at least a broken power law is require for a good fit (a = 1.75 and 1.41 shortward and longward of the break at ~4500 A). We detect a set of broad (FWHM ~ 400 km/s) absorption lines arising in the gas associated with M87. These are only lines from neutral and very low ionization species blueshifted by ~150 km/s relative to the M87 systemic velocity, indicating a net gas outflow and turbulence. The excitation sensitive emission line ratios suggest that shocks may be the dominant energy supplier. The nuclear source in M87 is significantly variable. From the FOS target acquisition data, we have established that the flux from the optical nucleus varies by a factor ~2 on time scales of ~2.5 months and by as much as 25% over 3 weeks, and remains unchanged (

Hubble Space Telescope observations of the centers of elliptical galaxies reveal that there are two types of ellipticals, divided by luminosity and morphology. The first type, denoted Type I (or core galaxies), have luminosity profiles which can be fitted accurately with a double power law for radii smaller than ≈ 1 kpc, and are characterized by high luminosity, relatively low central surface brightness, and low ellipticity. Type II galaxies (power law galaxies) have power law brightness profiles that rise steeply into the very center, and are characterized by high central surface brightness, high ellipticity, and relatively low luminosity. The Type II galaxies often have a distinct, bright, thin (r