Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-08T12:26:27.139Z Has data issue: false hasContentIssue false

Better Parallaxes and the Cosmic Distance Scale

Published online by Cambridge University Press:  07 August 2017

Sidney Van Den Bergh*
Affiliation:
Dominion Astrophysical Observatory 5071 West Saanich Road Victoria, B.C., V8X 4M6 Canada

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

It is generally agreed that the Hubble parameter lies in the range 50 < Ho (km s−1 Mpc−1) < 100. Recent observations, which are discussed in the present paper, favor Ho ≳ 75 km s−1 Mpc−1. Hubble Space Telescope observations of Cepheids in Virgo cluster galaxies will probably reduce the uncertainty in Ho to ∼ 20%. It should be possible to lower this remaining uncertainty in the Hubble parameter by strengthening the calibration of the Cepheid period-luminosity relation, the MV(RR) versus [Fe/H] relation of RR Lyrae stars, and the luminosity calibration of the subdwarf main sequence, by using parallaxes obtained with Hipparcos.

Type
2. Current and Future Needs for Very Accurate Astrometry
Copyright
Copyright © Kluwer 1995 

References

Ajhar, E.A., Lauer, T.R., Lynds, C.R., O'Neil, E.J., Faber, S.M., Grillmair, C.J., Baum, W.A., Ewald, S.P., Light, R.M., & Holtzman, J.A. 1994, poster paper presented at 184th AAS meeting.Google Scholar
Bernstein, G.M., Guhathakurta, P., Raychaudhury, S., Giovanelli, R., Haynes, M.P., Herter, T., & Vogt, N.P. 1994, AJ, 107, 1962 CrossRefGoogle Scholar
Caldwell, J.A.R., & Coulson, I.M. 1986, MNRAS, 218, 223 Google Scholar
Carney, B.W., Storm, J., & Jones, R.V. 1992, ApJ, 386, 663 Google Scholar
Freedman, W.L., & Madore, B.F. 1990, ApJ, 365, 186 Google Scholar
Fry, A.M., & Carney, B.W. 1994, BAAS, 26, 869 Google Scholar
Gould, A. 1994, ApJ, 426, 542 Google Scholar
Hoessel, J.G., Gunn, J.E., & Thuan, T.X. 1980, ApJ, 241, 486 Google Scholar
Jacoby, G.H., Branch, D., Ciardullo, R., Davies, R., Harris, W.E., Pierce, M.J., Pritchet, C.J., Tonry, J.L., & Welch, D.L. 1992, PASP, 104, 599 Google Scholar
Jacoby, G.H., & Pierce, M.J. 1994, NOAO Newsletter No. 38, p.1 Google Scholar
Jones, M. et al. 1993, Nature, 365, 320 CrossRefGoogle Scholar
Lauer, T.R., & Postman, M. 1992, ApJ, 400, L47 Google Scholar
Lu, N.Y., Salpeter, E.E., & Hoffman, G.L. 1994, ApJ, 426, 473 CrossRefGoogle Scholar
McMillan, R., Ciardullo, R., & Jacoby, G.H. 1993, ApJ, 416, 62 CrossRefGoogle Scholar
Méndez, R.H., Kudritzki, R.P., Ciardullo, R., & Jacoby, G.H. 1993, A&A, 275, 534 Google Scholar
Okamura, S., & Fukugita, M. 1991 in Primordial Nucleosynthesis and Evolution of the Early Universe, eds. Sato, K. and Audouze, J. (Kluwer, Dordrecht), 45 Google Scholar
Phillips, M.M. 1993, ApJ, 413, L105 CrossRefGoogle Scholar
Roland, J. 1994 in Proceedings of the 9th IAP Astrophysics Meeting, eds. Bouchet, F. and Lachièze-Rey, M., Editions frontières, Gif-sur-Yvette, in press Google Scholar
Sandage, A. 1993, AJ, 106, 703 Google Scholar
Sandage, A., & Tammann, G.A. 1994 preprint Google Scholar
Schmidt, B.P. 1994, private communication Google Scholar
Schmidt, B.P. et al. 1994, AJ, 107, 1444 Google Scholar
Tonry, J., & Schneider, D.P. 1988, AJ, 96, 807 Google Scholar
Turner, D.G. 1992, AJ 104, 1865 Google Scholar
Turner, D.G., Mandushev, G.I., & Forbes, D. 1994, AJ, 107, 1796 Google Scholar
van den Bergh, S. 1992, PASP, 104, 861 Google Scholar
van den Bergh, S. 1994, in preparation Google Scholar
Walker, A.R. 1992, ApJ, 390, L81 Google Scholar
Young, C.K., & Currie, M.J. 1994, MNRAS, 268, L11 Google Scholar