The Age and Size of the Universe

doi:10.1126/science.258.5081.421

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Science 16 October 1992:
Vol. 258. no. 5081, pp. 421 - 424
DOI: 10.1126/science.258.5081.421

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The Age and Size of the Universe

Sidney van den Bergh ¹

¹ Dominion Astrophysical Observatory, National Research Council of Canada, 5071 West Saanich Road, Victoria, British Columbia, V8X 4M6, Canada

Modern distance determinations to galaxies were reviewed andplaced on a uniform and self-consistent scale. Based on eightseparate but not entirely independent techniques, the distanceto the Virgo cluster was found to be 15.8 ± 1.1 megaparsec.Twelve different determinations yield a Coma/Virgo distanceratio of 5.52 ± 0.13 and hence a Coma distance of 87 ±6 megaparsec. With a cosmological redshift of 7210 kilometersper second, this gives a Hubble parameter H₀ (local) of 83 ±6 kilometers per second per megaparsec. From the velocity-distancerelation of rich clusters of galaxies, the ratio of the valueof H₀ (global) to the value of H₀ (local) was determined tobe 0.92 ± 0.08. In other words, the cluster data do notshow a statistically significant difference between the localand global values of the Hubble parameter. If one neverthelessadopts this relation between H₀ (global) and H₀ (local), thenthe value of H₀ (global) is 76 ± 9 kilometers per secondper megaparsec. This observed value differs at the $sim$ 3 $sgr$ level (where $sgr$ is the standard deviation of the distribution) from valuesin the range 36 $lsim$ H₀ $lsim$ 50 kilometers per second per megaparsec,which are derived from stellar evolutionary theory in conjunctionwith standard cosmological models with a density parameter ( $OHgr$ )that is equal to 1 and a cosmological constant ( $lgr$ ) that is equalto 0.