Cepheid and Maser Distances Agree
- From: Sam Wormley <swormley1@xxxxxxxxx>
- Date: Tue, 15 Aug 2006 00:06:15 GMT
Cepheid and Maser Distances Agree
http://www.astro.ucla.edu/~wright/cosmolog.htm#News
11 Aug 2006 - Macri et al. give a Cepheid distance to NGC 4258, where
Herrnstein et al. found a distance of 7.2 Mpc based on observing the
velocity and angular radius of a disk of masers around the nucleus, and
both the angular velocity and the centripetal acceleration of the
masers. Cepheids in NGC 4258 were 10.88 magnitudes fainter than
Cepheids of the same period in the LMC giving a distance of 48 +/- 2
(random) +/- 3 (systematic) kpc for the LMC. This agrees very well with
the light echo distance of 47 +/- 1 kpc for the LMC based on SN 1987A.
The final value for the Hubble constant is Ho = 74 +/- 3 (random) +/- 6
(systematic) km/sec/Mpc which agrees very well with the current
concordance models. Oddly enough, the second author on this paper is
also the second author on another recent result that claims a
significantly lower value for Ho. But none of the recent differences in
Ho determinations come close to the old Hubble constant wars between
the Sandage and de Vaucouleurs camps.
See: http://www.astro.ucla.edu/~wright/cosmolog.htm#News
with embedded links
.
- Follow-Ups:
- Re: Cepheid and Maser Distances Agree
- From: Bruce Scott TOK
- Re: Cepheid and Maser Distances Agree
- Prev by Date: Re: CMBR from big bang or aether??
- Next by Date: Re: Your secrets are safe here.
- Previous by thread: CMBR from big bang or aether??
- Next by thread: Re: Cepheid and Maser Distances Agree
- Index(es):
Relevant Pages
|
