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At all places where I have read of Moving Cluster Method for measuring distance to a cluster and once applied myself on data, I have been told that the method has been successfully applied only to Hyades cluster in Taurus.

hyades cluster moving cluster method

Question : What factor made the method unsuccessful for other known clusters?

Cheeku
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  • would you mind explain how the method works (mayby adding some link)? – Francesco Montesano Oct 27 '13 at 20:52
  • I'd suggest it is because, for the method to work, the cluster needs to be nearby and, in effect, relatively young (as open clusters get broken up otherwise) - eg the Hyades are about half the distance to the Pleiades and an order of magnitude younger than the Solar System. An additional factor is that the Hyades are a well-known yardstick for astronomical distances and so measuring them first would be a scientific priority. – adrianmcmenamin Feb 02 '14 at 14:32

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Do you know this paper? Mamajek (2005). "A Moving Cluster Distance to the Exoplanet 2M1207b in the TW Hydrae Association".

I'll risk an opinion: There is about a thousand clusters with kinematic measurements, but besides no more than half a dozen, all pm components are under 20 mas (milli-arcseconds) with errors more or less in the range 0.3-6 mas. Such errors are too high in relation to the pm values and as a result, the vectors will not converge.

Bruno Alessi
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