Orbital mechanics
The Whorl list — 1 messages, 1 voices, 06 Sep 2000
https://urth.darkrealm.vip/thread/whorl/1016

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Adam Stephanides — 06 Sep 2000, 11:40

> Alastair Reynolds wrote:
> Re: the orbital mechanics of Green/Blue - wasn't the best explanation,
> as worked out by someone here, that they're analogous to our moon and
> its small satellite partner Cruithne? It was pointed out that this
> had been written up (in Nature I think) early enough for Wolfe
> to have incorporated it into the series.

I was the one who suggested Cruithne as relevant to the Blue/Green
question.  (A couple of clarifications: it's not Earth's moon but Earth
that Cruithne is a companion of; and it's not a satellite of Earth, but
rather shares Earth's orbit in a sense, although its actual orbit is a
good deal more complicated.)  I argued that something like Cruithne's
orbit would explain the data in OBW, including the indications that at
conjunction Green moves perceptibly (from Blue) with respect to the
fixed stars in the course of a night.  However, nobody else seemed to
agree about Green's movement, or indeed about Cruithne as a likely
model.  Or if they did, they didn't post it.

>  Or was there some fatal flaw in that idea?

Not that I recall; people just didn't go for it.

The problem with this stuff (one reason why I stopped working on it) is
that you're dealing not with what is possible or probable, but with what
Wolfe thought was possible or probable, and we have no way of knowing
that short of asking him.  (The same applies to the inhumi
transportation question.)

> And Robert Borski wrote:
> Also for mantis: where does the Whorl orbit in your opinion? Around Blue?
> Green? Or some Lagrange point between (or outside?) the binary planet
> system?

As I once posted, the fact that conjunction between Blue and Green
occurs only once every six years seems clearly to imply that Blue and
Green do not form a binary system, but orbit the Short Sun
independently; and this seems to be the consensus on the list, as well. 
As for the Whorl, the since its conjunctions with Blue are even rarer,
and it approaches less closely to Green at conjunction, I assumed that
it too orbited the Short Sun independently.  Do you have any reason for
thinking otherwise?

--Adam

*This is WHORL, for discussion of Gene Wolfe's Book of the Long Sun.

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