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We present here the Ðnal results of the Hubble Space T elescope (HST) Key Project to measure the Hubble constant. We summarize our method, the results, and the uncertainties, tabulate our revised distances , and give the implications of these results for cosmology. Our results are based on a Cepheid calibration of several secondary distance methods applied(More)
The possibility that the masses M • of supermassive black holes (SBHs) correlate with the total gravitational mass of their host galaxy, or the mass M DM of the dark matter halo in which they presumably formed, is investigated using a sample of 16 spiral and 20 elliptical galaxies. The bulge velocity dispersion σ c , typically defined within an aperture of(More)
Three cDNA clones (pCel 10, pCel 20 and pCel 30), each encoding different endo-beta-1,4-glucanases in peach, were obtained by RT-PCR and their expression investigated by northern analysis during leaf and fruit abscission and during fruit development. This analysis allowed the detection of only the pCel 10-related mRNA. A 2.2 kb transcript accumulated in(More)
Cepheid variable stars pulsate in a way that is correlated with their intrinsic luminosity, making them useful as 'standard candles' for determining distances to galaxies; the potential systematic uncertainties in the resulting distances have been estimated to be only 8-10%. They have played a crucial role in establishing the extragalactic distance scale(More)
We present a detailed analysis of the morphology, isophotal parameters and surface brightness profiles for 100 early-type members of the Virgo Cluster, from dwarfs (M B = −15.1 mag) to giants (M B = −21.8 mag). Each galaxy has been imaged in two filters, closely resembling the Sloan g and z passbands, using the Advanced Camera for Surveys on board the(More)
Imaging surveys with the Hubble Space Telescope (HST) have shown that ≈ 50–80% of low-and intermediate-luminosity galaxies contain a compact stellar nucleus at their center, regardless of host galaxy morphological type. We combine HST imaging for early-type galaxies from the ACS Virgo Cluster Survey with ground-based long-slit spectra from KPNO to show that(More)
The ACS Virgo Cluster Survey is a Hubble Space Telescope program to obtain high-resolution imaging, in widely separated bandpasses (F475W ≈ g and F850LP ≈ z), for 100 early-type members of the Virgo Cluster, spanning a range of ≈ 460 in blue luminosity. We use this large, homogenous dataset to examine the innermost structure of these galaxies and to(More)
Metal-poor globular clusters (GCs) are our local link to the earliest epochs of star formation and galaxy building. Studies of extragalactic GC systems using deep, high-quality imaging have revealed a small but significant slope to the color-magnitude relation for metal-poor GCs in a number of galaxies. We present a study of the M87 GC system using deep,(More)