Cosmic Expansion and Ho: A Retro- and Pro-Spective Note
Abstract
Attempts to measure extragalactic distances over the last 90 years are briefly described. It follows a short history of the discovery of the expansion of space. Reasons are discussed for the decrease of the Hubble constant from Ho~500 originally to Ho<~60 at present. Remaining problems with Cepheids as local distance calibrators are outlined.
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