Talk:Standard candle

"Recently"
The section on "Eclipsing binaries" uses relative descriptions of time: "In the last decade ... Recently". This isn't a good idea, as it means the article ages badly. It would be much better (and more future-proof) if it gave approximate dates instead. -- Finlay McWalter | Talk 22:40, 15 December 2006 (UTC)
 * How bout, "since the 1990s"? Sagittarian Milky Way 06:51, 25 March 2007 (UTC)

Population I/II Cepheids
I think that the last paragraph is incorrect; however, I am not an expert. My understanding is that:

- The Population II Cepheids, or W Virginis variables, have lower luminosity, than the Population I, or classical, Cepheid variables.

- The distances in the Milky Way had been measured using W Virginis variables (and RR Lyrae variables, also Population II stars).

- The extra-galactic distances had been measured using classical Cepheid variables.

- When W. Baade discovered the star populations, only the extra-galactic distances were affected. The distances in the Milky Way were not affected. JTMnen 07:57, 28 August 2007 (UTC)

Measuring distances
In order to further developing this article, it may be a good idea to include an extensive section on measuring cosmic distances. I think this section should discuss each of the significant methods, along with their respective strengths and weaknesses (in terms of accuracy and range). Here is a candidate list: These can probably be sub-grouped by range. Is there anything else I need to include? Thanks.&mdash;RJH (talk) 16:50, 18 October 2008 (UTC)
 * Trigonometric parallax
 * Variables: Eclipsing binary, Cepheid variable, RR Lyrae variables, Novae
 * Planetary nebula luminosity function
 * Globular Clusters (via main sequence curve)
 * Tip of the red giant branch
 * VLBI: Radio jet proper motion
 * VLBI: Maser proper motion
 * Sunyaev-Zel'dovich effect
 * Surface brightness fluctuation
 * Tully-Fisher relation
 * D-sigma relation (ellipticals)
 * X-ray burster
 * Brightest cluster galaxy
 * Type Ia supernovae
 * Gravitationally lensed quasars
 * Gamma ray bursters
 * Coalescing massive black holes