Is big moon in sky plausible?
Every time I see an image like the giant moon on the cover of the
August 2003 issue of Locus, I think it makes a wonderful image but
then I ask, but can that really happen?
Which leads me to ask a couple of questions.
1) If a moon is orbiting near Roches' limit, what does it look like?
I guess, kind of odd, noticeably egg-shaped. Not nicely spherical
as on the Locus cover.
2) Is there a characteristic solid-angular size, a maximum limit on
how large an orbiting neighbor can appear, before it begins to
break up? I.e., how much sky it fills?
Seems to me, I recall an sf story which had two worlds orbiting
practically in contact, with an ocean spilling back and forth between
them. They shared an atmosphere. Robert Forward, I think.
Cheers -- Martha Adams
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