EXCURSIONS ON THE PLANETS—RUDAUX 187 
But it is not the contour, the general outline of these moonscapes, 
which strikes the human eye with astonishment; it is the atmospheric 
conditions. We know that this globe, if not totally without an 
atmosphere, at least possesses none which we can detect. Conse- 
quently, since there is no air to scatter the light coming from the 
sun, this orb of day is enthroned in a black sky, dotted with stars as 
if at night. Moreover, a harsh light marks every detail, near or 
distant, with the same dry and insistent sharpness. How different 
is this view from those on our earth where the different distances 
merge harmoniously in blending vapors. It is surely in this man- 
ner that the eye will be most surprised, even though it is the eye of 
the most rabid impressionistic artist. Let the eye be that of an 
astronomer and his marvelling will be without end. Here our 
atmosphere interposes a serious obstacle to his contemplation of the 
heavens; it obstructs greatly the light coming from the stars, 
troubles their images, and even limits their visibility. It is, indeed, 
a real veil placed before his eyes. Upon the moon this veil is absent 
and the heavens shine in striking majesty. If the eyes are not 
dazzled by the blinding rays coming without hindrance directly 
from the sun, the unfathomable space will appear riddled with 
stars, more countless than on the earth, and these myriads of stars 
will show no scintillation. What a wonderful richness and what 
facility for observation would be the lot of the fortunate astronomer 
inhabiting the moon. Further, because of this same lack of an 
atmosphere, the rising and setting of the sun would offer appear- 
ances entirely unknown on the earth. At sunrise there would first 
appear the radiant glory of the sun’s corona; next those gigantic 
rose-colored flames, the protuberances, will rise above the horizon. 
On the earth these phenomena are visible to the unaided eye only 
during the short duration of a solar eclipse. Stretching far up- 
wards, like a great extension of the corona, will be seen the immense 
spindle-shaped zodiacal light, a phenomenon about which our ideas 
are still somewhat confused because of the difficulties in the way of 
its observation from the earth. 
This grand spectacle, of which Plate 1 is a very unsatisfactory 
replica, we can leisurely admire. For the rotation of the moon takes 
the same length of time as its revolutions about the earth—for which 
reason she always turns the same face toward us. This rotation time 
is twenty-seven times less rapid than that of the earth. The appar- 
ent movement of the heavens is of course slowed down in the same 
proportion and the stars will appear to rise and set with a majestic 
slowness. ‘Though the sky itself seems almest motionless, there is one 
celestial body which will appear to be at rest—our own earth. This 
is really not quite true, since, because of the unequal movement of 
the moon in its eccentric orbit, the terrestrial globe appears to oscil- 
