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3.1. Relative Distance Methods

One piece of good news is that the several methods of measuring the relative distances to galaxies now mostly seem to be consistent with each other. These methods use either ``standard candles'' or empirical relations between two measurable properties of a galaxy, one distance-independent and the other distance-dependent. The favorite standard candle is SNe Ia, and observers are now in good agreement. Taking account of an empirical relationship between the SNe Ia light curve shape and maximum luminosity leads to h = 0.65 ± 0.06 (Riess, Press, & Kirshner 1996), h = 0.64+0.08-0.06 (Jha et al. 1999), or h = 0.63 ± 0.03 (Hamuy et al. 1996, Phillips et al. 1999), and the slightly lower value mentioned above from the latest analysis coauthored by Sandage and Tammann agrees within the errors. The HST Key Project result using SNe Ia is h = 0.65 ± 0.02 ± 0.05, where the first error quoted is statistical and the second is systematic (Gibson et al. 1999), and their luminosity-metallicity relationship (Kennicutt et al. 1998) has been used (this lowers h by 4%). Some of the other relative distance methods are based on old stellar populations: the tip of the red giant branch (TRGB), the planetary nebula luminosity function (PNLF), the globular cluster luminosity function (GCLF), and the surface brightness fluctuation method (SBF). The HST Key Project result using these old star standard candles is h = 0.66 ± 0.04 ± 0.06. The old favorite empirical relation used as a relative distance indicator is the Tully-Fisher relation between the rotation velocity and luminosity of spiral galaxies. The ``final'' value of the Hubble constant from the HST Key Project taking all of these into account is h = 0.71 ± 0.06 (Ferrarese et al. 1999, and this conference, for a nice summary).