The people of the paper says that the cluster lies at a distance of 9 Gly, but they don't indicate what kind of distance. I suppose that they mean comoving distance, but I'm not sure. Anybody knows the redshift of this cluster? I could transform the redshift to comoving distance, that is the distance that I like more
blobrana, you're the man Ok introducing this cipher in Ned Wright's calculator http://www.astro.ucla.edu/~wright/CosmoCalc.html for a universe with H=71, Omega-matter=0.27, Omega-Lambda=0.73, flat, it gives me a comoving distance of 13.7 Gly It gives also two other distances (luminosity and angular size) that don't mach either with the 9 Gly of the article. Ummmm. I'm always suspicious of distances given in popular articles....
Hum, <font color=pink>< must bookmark ></font> neat link... Hum did you use `flat`? the `light travel time` is shown as 9.061 Gyr. While the `comoving radial distance` is shown as 13.728 Gly. ( the links explain the difference) <font color=pink>< /must bookmark ></font>
yeah comoving radial distance is the same as comoving distance. Perhaps they were mentioning the light travel time in the article, though is a kind of measure rarely used in articles. Well I used flat. The Universe is flat. Omega=1.
Definitely the article is wrong. The most distant galaxy cluster was discovered a couple of weeks ago and has a redshift z=5.7 http://www.universetoday.com/am/publish/galaxy_clusters_early.html?1722005
Hum, yeah, i think it the main point with the new cluster was that they were `highly structured` or `highly evolved` after only a few billion years. The galaxies in the cluster are red and elliptical, which means that they are quite `old`... A puzzle indeed.