s, of Andromeda, of
Cassiopeia, are of this order. These, with the former, constitute the
principal outlines of the constellations visible to us.

Then follow the third and fourth magnitudes, and so on.

* * * * *

The following table gives a summary of the series, down to the sixth
magnitude, which is the limit of visibility for the unaided human eye:

19 stars of first magnitude.
59 of second magnitude.
182 of third magnitude.
530 of fourth magnitude.
1,600 of fifth magnitude.
4,800 of sixth magnitude.

This makes a total of some seven thousand stars visible to the unaided
eye. It will be seen that each series is, roughly speaking, three times
as populated as that preceding it; consequently, if we multiply the
number of any class by three, we obtain the approximate number of stars
that make up the class succeeding it.

Seven thousand stars! It is an imposing figure, when one reflects that
all these lucid points are suns, as enormous as they are potent, as
incandescent as our own (which exceeds the volume of the Earth by more
than a million times), distant centers of light and heat, exerting their
attraction on unknown systems. And yet it is generally imagined that
millions of stars are visible in the firmament. This is an illusion;
even the best vision is unable to distinguish stars below the sixth
magnitude, and ordinary sight is far from discovering all of these.

Again, seven thousand stars for the whole Heavens makes only three
thousand five hundred for half the sky. And we can only see one
celestial hemisphere at a time. Moreover, toward the horizon, the vapor
of the atmosphere veils the little stars of sixth magnitude. In reality,
we never see at a given moment more than three thousand stars. This
number is below that of the population of a small town.

* * * * *

But celestial space is unlimited, and we must not suppose that these
seven thousand stars that fascinate our eyes and enrich our Heavens,
without which our nights would be black, dark, and empty,[5] comprise
the whole of Creation. They only represent the vestibule of the temple.

Where our vision is arrested, a larger, more powerful eye, that is
developing from century to century, plunges its analyzing gaze into the
abysses, and reflects back to the insatiable curiosity of science the
light of the innumerable