Quasar distances

For near-by objects we can measure actual distance by triangulation. But this is limited to about 1000 light years presently (by the combination of the 2 AU base line of Earth's orbit and the pointing accuracy of our telescopes). For more distant objects we must infer the distance by various indirect methods.

* Measured brightness, especially of certain variable star types, seems to work well for objects beyond 1000 ly but within our galaxy and its neighbors.

* Red shift is the primary method used for objects thought to be really distant. But as you have seen this may not be very accurate for some objects, like quasars.

LB

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Rudolf</i>
<br />Anyone got any comments on this?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">For our take on this (which supports Arp's view), see our web site article "Quasars: Near vs. Far" at metaresearch.org/cosmology/QuasarsNearVersusFar.asp -|Tom|-

Rudolf, The reason quasars are said to be at the distance claimed is due to measuring the redshift and assuming it is caused by velocity. This velocity so they say is caused by the expansion of the universe and the further away something is from Earth the more it redshifts. As anyone can see if they look at this model in order for the universe to be the size it is the universe is expanding at the speed of light. It is and has always expanded at this rate.