Steps toward the Hubble constant. VIII - The global value

摘要: The problem of determining the global Hubble constant is approached by using two distance indicators whose dispersion in absolute magnitude small, and hence which are virtually free Malmquist bias. New data presented on mean absolute-magnitude brightest individual red blue supergiant stars very nearby galaxies, calibrated relative to Cepheids. results used calibrate maximum for well-observed Type I supernovae (SNe I). velocity-relative diagram 16 SNe with known apparent magnitudes then distances IC 4182 NGC 4214, result that equals 50 + or - 7 km per second megaparsec. compared age globular clusters Galaxy show cosmological evolutionary time scales now closely agree.