Christian Froeschlin <chr### [at] chrfrde> wrote:
> looks sleek! I'm not sure I'm getting the animation at the
> intended aspect ratio though, both stars seem very elongated.
> I think they should be more shaped like droplets, with the outer
> halfs being mostly round, as in this roche lobe diagram:
>
>    http://www.airynothing.com/high_energy_tutorial/sources/binaries.html

In fact I am actually using the Roche potential for the isosurfaces. The
elongation did surprise me at first (I encountered this when I generated models
of these for an add-on to the Celestia space simulator), but as far as I can
tell it does seem to be a feature of this potential.

On the other hand, this shape does not represent a real binary: effectively I am
modelling the system as a massless fluid surrounding two point masses in
Keplerian orbit. Since the real stars have a distribution of mass, the actual
shape would change. However modelling this accurately is going to be a
nightmare... I'd want at least a PhD at the end of all that. :-)

Anyway, just in case you are getting aspect ratio distortion, I've attached a
render of the first frame, albeit with toned-down coronae.

> Also, they might be a bit too close and uniformly merged.
> I think they would touch with a thinner streak of streaming
> material which probably also looks different from the star.

Judging by the catalogue of contact binaries at
http://www.mporzio.astro.it/~maceroni/wumacat.html there seem to be a wide range
of fill-out factors - this rendering is based on RW Comae Berenices which has
quite a high fill-out factor. The idea of modifying the texture to put some
evidence of material flowing across the "neck" is a good one though.

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