Mike Rhino ) wrote:
: "Henry Spencer" wrote in message
: ...
: In article ,
: johnhare wrote:
: It seems to me that a tide-locked body in a dawn dusk polar
: orbit could well have a permanantly dark side...
:
: Mmm, yes, provided the orbit was sun-synchronous -- precesses once around
: the primary per primary orbital period -- which requires a rather exact
: match between the orbit characteristics and the primary's equatorial
: bulge. I can't see that persisting for very long, however; the exact
: match is not very stable.

: Suppose that it isn't an exact match so that one day lasts 100 years. It
: would still be an interesting place.

How about a case where one of the poles points in the direction of the
orbital plane? IOW, at one point in the orbit the north pole points at the
sun and on the other side of the orbit the south pole points toward the
sun. Unlike the Earth's or Mars' ~25 deg. axis tilt this other is more on
the order of a 90 deg. axis tilt.

Eric