Never .
/ Visible
/
South
Pole

THE CELESTIAL SPHERE.]

The outline of this unmapped region must therefore correspond roughly to
the horizon of the place where the constellations were originally
designed, or at least be roughly parallel to it, since we may well
suppose that stars which only rose two or three degrees above that
horizon might have been neglected.

From this we learn that the constellations were designed by people
living not very far from the 40th parallel of north latitude, not
further south than the 37th or 36th. This is important, as it shows that
they did not originate in ancient Egypt or India, nor even in the city
of Babylon, which is in latitude 32-1/2 deg..[157:1]

But this vacant space reveals another fact of even more importance. It
gives us a hint as to the date when the constellations were designed.

An observer in north latitude 40 deg. at the present time would be very far
from seeing all the stars included in the forty-eight constellations. He
would see nothing at all of the constellation of the Altar, and a good
deal of that of the Centaur would be hidden from him.

On the other hand, there are some bright constellations, such as the
Phoenix and the Crane, unknown to the ancients, which would come within
his range of vision. This is due to what is known as "precession;" a
slow movement of the axis upon which the earth rotates. In consequence
of this, the pole of the heavens seems to trace out a circle amongst the
stars which it takes 25,800 years to complete. It is therefore a matter
of very simple calculation to find the position of the south pole of the
heavens at any given date, past or future, and we find that the centre
of the unmapped space was the south pole of the heavens something like
4,600 years ago, that is to say about 2,700 B.C.

It is, of course, not possible to fix either time or latitude very
closely, since the limits of the unmapped space are a a little vague.
But it is significant that if we take a celestial globe, arranged so as
to represent the heavens for the time 2,700 B.C., and for north latitude
40 deg., we find several striking relations. First of all, the Great Dragon
then linked together the north pole of the celestial equator, and the
north pole of the ecliptic; it was as nearly as possible symmetrical
with regar