After passing the asteroids in our system, we come to Jupiter, the largest of the planets. Jupiter often shines more brightly than Venus. It is more than one thousand times larger than the earth, and is seen during most of the year. The year of Jupiter; that is, the time which is required for its journey around the sun, is almost twelve of our years. Day and night are equal, and of about five hours each, and there is probably no change of seasons. But Jupiter seems to be to-day a still highly heated body, as our earth was very many ages ago, and its surface is disturbed by terrific storms. Jupiter is accompanied by four moons, and its globe is surrounded by several dark belts, which seem variable in number, but apparently belong to its surface. The belts somewhat resemble sun-spots, and indeed the whole planet is considered by astronomers to be much more like the sun than like our earth. The reason that Jupiter does not have changes of season is that the inclination of the planet to its orbit is very slight. When we consider that Jupiter turns on its axis in less than half the time that our earth requires for a rotation, and is also so very much greater in diameter than our earth, we will realize how marvellously rapid its daily motion must be. Next to Jupiter in place, and next also in size, is Saturn, the sixth planet from the sun. Ancient astronomers supposed that with Saturn our solar system ended. Saturn has eight moons placed at different distances, and is further distinguished by a very beautiful triple ring surrounding the entire planet on its equatorial line. Within this glowing triple ring the planet turns, and the rings themselves are carried round the planet in a circular movement of still greater swiftness. These rings are not always visible, as they, like their planet, shine by the reflection of sunlight, and so are seen only when the sun and earth are both on the same side of the planet. In 1781 Sir William Herschel, the English astronomer, who had made for himself a very fine telescope, discovered another planet. At first he supposed this was not a planet but a comet. Finally it was received into the family of the planets and named Uranus. Uranus is much smaller than Saturn, but many times larger than the earth. A year on Uranus is eighty-four of our years; that is, it takes Uranus eighty-four years to make its circuit of the sun.