Computer Science
Scientific paper
Apr 1969
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1969natur.222..158d&link_type=abstract
Nature, Volume 222, Issue 5189, pp. 158 (1969).
Computer Science
Scientific paper
SANDAGE has called my attention to a passage in the recent paper by Peters and I on the solar motion1, which might lead to misunderstanding. In the section ``Solutions with a Hubble Constant'' the numerical values of H ranging between 109 and 143 are not to be construed as new, independent determinations possibly conflicting with the values of the order of 50-80 which are favoured by Sandage. We made it clear (or we thought we had) that our solutions for H are strictly relative to the distance scale used in the survey of nearby groups2,3. This distance scale rests in turn entirely on the 1961 values of Sandage for the distances of galaxies in the local group and in some of the nearest groups4. Any change in this basic yardstick will be directly reflected in the derived values of H; for example, if all distance moduli in the local group were increased by 0.5 magnitude, the values of H would be decreased by 26 per cent. Such a change is, perhaps, not precluded by existing data. The recent work of Sandage on the Virgo cluster ellipticals5,6 suggests an apparent modulus of 31.1, or 0.6 magnitude greater than the value in the survey of groups. As Sandage himself readily admits5,6, however, the absolute calibration of the distance scale, and therefore of H, is still uncertain by perhaps 50 per cent. No one should therefore be particularly surprised if different solutions placing more or less weight on different distance indicators lead to values of H ranging all the way from 50-130 km/s Mpc-1. Sandage emphasizes that the method depending on an absolute calibration of the brightest elliptical galaxies in large clusters bypasses the difficulties introduced by the local anisotropy and should eventually lead to an unbiased solution (if statistical and evolutionary effects are not as serious as some authors have claimed). According to Sandage5,6 the dispersion of this criterion is less than 0.3 magnitude. For comparison we should note that the mean error of distance moduli in the survey of nearby groups derived by comparison with independent determinations (by Holmberg and van den Bergh) on the same distance scale is only 0.15 magnitude; this is what we meant by ``reliable estimates of relative distances'' for the groups. The absolute calibration of the distance scale is an entirely different problem.
No associations
LandOfFree
Solar Motion with Respect to the Galaxies, and the Hubble Constant does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Solar Motion with Respect to the Galaxies, and the Hubble Constant, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Solar Motion with Respect to the Galaxies, and the Hubble Constant will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1814677