Term: sky map
SC001 and SC002 map the celestial
sphere, but they don't tell us what part of the celestial sphere
can be seen at a particular time at a particular location.
(That's a plus: these maps can be sold anywhere, and if you can find one star
both in the sky and on the maps, you should be able to map the rest
of the sky as the relative position of the stars is well presented
by the SC maps.) The sky map is a stereographic projection of the
hemisphere of the sky onto a circular map. Zenith is at the center
of the map; the edges are where the sky ends: the horizon. Just as
with SC001 east and west seem reversed because this map is intended to
be looked up at rather than down at. Such maps vary both with
location and time...they can not be printed up and sold bulk.
One nice way to get such a map is from
Your Sky (John Walker, Fourmilab).
You'll need to tell them your location and the day and time for
the map. Remember the stars in the sky are on the move!
The below diagram shows how we could make a stereographic projection of the
sky.
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