JDG wrote:
>
>> Not Thalia - this would be a _Fall_ constellation.
>
> Ah yes, I was thinking of Earth where a Fall constellation would also be a
> winter constellation.
>
Again, no. There are Winter, Summer, Fall and Spring constellations - 
the difference is that a typical Winter constellation might be seen in
other seasons [depending on the latitude of the observer and the 
declination of the constellation]. And, rigorously, the constellations
distribute all over the sky, so that between a Winter and a Fall constellation
there may be a constellation that is visible in the second half of Fall and
in the first half of Winter, etc.

>Is it possible, however, that due to the eccentric orbit, a constellation
>would be visible in the Fall and invisible for most of summer and winter?
>
It does not depend on the eccentricity of the orbit, because Winter/Spring/
Summer/Fall for Stratos are defined by the true anomaly, so that the sky is
divided in four geometrically equal parts - that's the reason why Winter takes
half the year [Kepler's 2nd law: the area covered by the orbit is proportional
to time]


I've attached a small gif to illustrate what I mean [using a 0.5 eccentricity
for the orbit]. Sorry for those that get brin-l by digest mode...

Ah, the answer is *yes* - but it would have to be a constellation in
the opposite hemisphere, for example [in this case, where the Prison
is located at about 40 deg North] a southern constellation.

Thalia, however, is a northern constellation [declination ~ 40 deg].
and it would be visible *all* the year, but not *all* the nights.

Alberto Monteiro

Attachment: stratosorbit.gif
Description: GIF image

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