The moon having no atmosphere, this absence of vaporous covering had consequences already pointed out. There is no twilight on its surface, night following day and day following night, with the suddenness of a lamp extinguished or lighted in profound darkness. There is no transition from cold to heat: the temperature falls in one instant from boiling water heat to the cold of space.
Another consequence of this absence of air is the following:—Absolute darkness reigns where the sun's rays do not penetrate. What is called diffused light upon the earth, the luminous matter that the air holds in suspension, which creates twilights and dawns, which produces shadows, penumbrae, and all the magic of the chiaro-oscuro, does not exist upon the moon. Hence the harshness of contrasts that only admit two colours, black and white. If a Selenite shades his eyes from the solar rays the sky appears absolutely dark, and the stars shine as in the darkest nights.
The impression produced on Barbicane and his two friends by this strange state of things may well be imagined. They did not know how to use their eyes. They could no longer seize the respective distances in perspective. A lunar landscape, which does not soften the phenomenon of the chiaro-oscuro, could not be painted by a landscape-painter of the earth. It would be nothing but blots of ink upon white paper.
This aspect of things did not alter even when the projectile, then at the altitude of the 80th degree, was only separated from the moon by a distance of fifty miles, not even when, at 5 a.m., it passed at less than twenty-five miles from the mountain of Gioja, a distance which the telescopes reduced to half-a-mile. It seemed as if they could have touched the moon. It appeared impossible that before long the projectile should not knock against it, if only at the North Pole, where the brilliant mountains were clearly outlined against the dark background of the sky. Michel Ardan wanted to open one of the port-lights and jump upon the lunar surface. What was a fall of twelve leagues? He thought nothing of that. It would, however, have been a useless attempt, for if the projectile was not going to reach any point on the satellite, Michel would have been hurled along by its movement, and not have reached it either.
At that moment, 6 a.m., the lunar pole appeared. Only half the disc, brilliantly lighted, appeared to the travellers, whilst the other half disappeared in the darkness. The projectile suddenly passed the line of demarcation between intense light and absolute darkness, and was suddenly plunged into the profoundest night.
CHAPTER XIV.
A NIGHT OF THREE HUNDRED AND FIFTY-FOUR HOURS AND A HALF.
At the moment this phenomenon took place the projectile was grazing the moon's North Pole, at less that twenty-five miles' distance. A few seconds had, therefore, sufficed to plunge it into the absolute darkness of space. The transition had taken place so rapidly, without gradations of light or attenuation of the luminous undulations, that the orb seemed to have been blown out by a powerful gust.
"The moon has melted, disappeared!" cried Michel Ardan, wonder-stricken.
In fact, no ray of light or shade had appeared on the disc, formerly so brilliant. The obscurity was complete, and rendered deeper still by the shining of the stars. It was the darkness of lunar night, which lasts 354 hours and a half on each point of the disc—a long night, the result of the equality of the movements of translation and rotation of the moon, the one upon herself, the other round the earth. The projectile in the satellite's cone of shadow was no longer under the action of the solar rays.