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From: ahenden@magnus.acs.ohio-state.edu (Arne A Henden)
Newsgroups: sci.electronics
Subject: Re: How to tell distance of Stars
Summary: this belongs in sci.astro
Message-ID: <1991May16.133950.9685@magnus.acs.ohio-state.edu>
Date: 16 May 91 13:39:50 GMT
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Peter Kent writes:
>The Doppler red-shift method has been used for decades to determine the
>distance of stars from earth, but can anyone out there explain how to 
>correct for the following scenario?:
[deleted]

Much as I enjoy this kind of discussion, it belongs in sci.astro.

As for the question, astronomers NEVER use red-shift for individual
stars, only for galaxies.  The scenario you describe is why red-shift
distances have large errors even working with galaxies, as they often
belong to clusters and have local velocities as well as the recession
velocity.  In general, you can determine the distance to a group of
galaxies this way, as you take the average of all the galaxies in
the group which should average out the 'rotation' effect.

Can we move further discussion elsewhere?  Thanks.