A REVIEW OF DISTANCE INDICATOR DIFFICULTIES

G. Paturel
Observatoire de Lyon, Université Claude-Bernard Lyon1
F69561 Saint-Genis Laval, France

Abstract:

Participants to this meeting presented their results about the distance scale and about the Hubble constant. It was quite interesting because the agreement between different approaches is far from being satisfying. The discrepancy between extreme values of the Hubble constant is smaller than before, but there is no consensus so far. In this paper we will try to understand the origin of remaining discrepancies.

• INTRODUCTION
• GEOMETRICAL CALIBRATION
  • Trigonometric parallaxes
  • Ring of the SN1987A
• EXTENSION TO LARGER DISTANCES
  • Method based on a relation M=a logP +b
  • Method based on luminosity function of a class of objects
  • Method independent of limiting apparent magnitude
• CONCLUSION