The astronomer smiled again as he took the paper back. Meanwhile the Astronef was rushing upward like a meteor through the clouds. In ten minutes the limits of the Jovian atmosphere were passed. Stars and suns and planets blazed out of the black vault of Space, and the great disc of the World that Is to Be once more covered the floor of Space beneath them—an ocean of cloud, covering continents of lava and seas of flame, the scene of the natal throes of a world which some day will be.
They passed Io and Europa, which changed from new to full moons as they sped by towards the Sun, and then the golden yellow crescent of Ganymede also began to fill out to the half and full disc, and by the tenth hour of Earth-time, after they had risen from its surface, the Astronef was once more lying beside the gate of the Crystal City.
At midnight on the second night after their return, the ringed shape of Saturn, attended by his eight satellites, hung in the zenith magnificently inviting. The Astronef's engines had been replenished after the exhaustion of their struggle with the might of Jupiter. They said farewell to their friends of the dying world. The doors of the air-chamber closed. The signal tinkled in the engine-room, and a few moments later a blurr of white lights on the brown background of the surrounding desert was all they could see of the Crystal City under whose domes they had seen and learnt so much.
CHAPTER XVII
The relative position of the two giants of the Solar System at the moment when the Astronef left the surface of Ganymede, was such that she had to make a journey of rather more than 340,000,000 miles before she passed within the confines of the Saturnine System.
At first her speed, as shown by the observations which Redgrave took with the instruments which Professor Rennick had designed for the purpose, was comparatively slow. This was due to the tremendous pull of Jupiter and its four moons on the fabric of the vessel. The backward drag rapidly decreased as the pull of Saturn and his system began to overmaster that of Jupiter.
It so happened, too, that Uranus, the next outer planet of the Solar System, 1,700,000,000 miles away from the Sun, was approaching its conjunction with Saturn, and so assisted in producing a constant acceleration of speed.
Jupiter and his satellites dropped behind, sinking, as it seemed to the wanderers, down into the bottomless gulf of Space, but still forming by far the most brilliant and splendid object in the skies. The far-distant Sun, which, seen from the Saturnian System, has only about a nineteenth of the superficial extent which it presents to the Earth, dwindled away rapidly until it began to look like a huge planet, with the Earth, Venus, Mars, and Mercury as satellites. Beyond the orbit of Saturn, Uranus, with his eight moons, was shining with the lustre of a star of the first magnitude, and far above and beyond him again hung the pale disc of Neptune, the Outer Guard of the Solar System, separated from the Sun by a gulf of more than 2,750,000,000 miles.
When two-thirds of the distance between Jupiter and Saturn had been traversed, Ringed Orb lay beneath them like a vast globe surrounded by an enormous circular ocean of many-coloured fire, divided, as it were, by circular shores of shade and darkness. On the side opposite to them a gigantic conical shadow extended beyond the confines of the ocean of light. It was the shadow of half the globe of Saturn cast by the Sun across his rings. Three little dark spots were also travelling across the surface of the rings. They were the shadows of Mimas, Enceladus, and Tethys, the three inner satellites. Japetus, the most distant, which revolves at a distance ten times greater than that of the Moon from the Earth, was rising to their left above the edge of the rings, a pale, yellow, little disc shining feebly against the black background of Space. The rest of the eight satellites were hidden behind the enormous bulk of the planet and the infinitely vaster area of the rings.