The status of the determination of the Hubble constant is reviewed , setting out the evidence for the long distance scale with H _ { 0 } = 55 \pm 5 .
In parallel , various precepts used by others , said to favor the short distance scale with H _ { 0 } > 70 are discussed .
The strongest evidence for the long scale are ( 1 ) the calibration of the peak absolute magnitude of type Ia supernovae with their Hubble diagram tied to the remote cosmic kinematic frame , ( 2 ) the distance to the Virgo cluster by six largely independent methods including Tully-Fisher using a complete cluster sample and a new calibration using recent HST Cepheid data , and ( 3 ) field spirals binned by luminosity class , also calibrated using Cepheid distances .
The three methods give H _ { 0 } = 56 \pm 3 , 55 \pm 2 , and 53 \pm 3 ( internal errors ) . H _ { 0 } does not vary significantly over scales from 10-500 Mpc . H _ { 0 } does not increase outward , as appearances using field galaxies would give if the raw data were not corrected for observational selection bias .

Higher values of H _ { 0 } still in the literature are based on ( 1 ) an untenably small distance to the Virgo cluster claimed by equating ( against newly available evidence ) the Cepheid distance of M100 with the mean distance of the cluster , ( 2 ) an untenably large Virgo cluster velocity tied to the remote cosmic kinematic frame , ( 3 ) a questionable route through the Coma cluster on the assumption that its random motion can be neglected at its assumed distance , ( 4 ) an incorrect precept that the Cepheid distance to NGC 1365 , a possible member of the Fornax cluster , gives the distance to NGC 1613 , parent to two SNe Ia , calibrating them , ( 5 ) an unjustified reliance on planetary nebulae and surface brightness fluctuations as distance indicators at the present stage of their calibration , and ( 6 ) either an underestimation or a neglect of the importance of observational selection bias in flux-limited samples , both for cluster galaxies ( the Teerikorpi cluster incompleteness bias ) , or for field galaxies ( the Malmquist bias ) .
There is no valid evidence for H _ { 0 } > 70 .

The status of the time scale test is reviewed using recent discussions of the age of globular clusters based on seven studies since 1993 .
The result is 13-14 ( \pm 2 ) Gyr for the age of the Galactic globular cluster system .
Even with a gestation period of the Galaxy of 1 Gyr , there is no time scale crisis in cosmology provided that q _ { 0 } < 0.3 , H _ { 0 } = 55 , and \Lambda = 0 .