It is a privilege of astronomers to be able to predict events that will happen in thousands of years to come, and to describe things accurately though they never saw them, and though nobody else has ever seen them either. No one has ever yet got to the North Pole, but whenever they do, we are able to tell them much of what they will see there. We may leave it to Jules Verne to describe how the journey is to be made, and how the party are to be kept alive at the North Pole. I shall give a picture of the changes of the seasons, and of the appearance in the stars, as seen from thence.
We shall, therefore, prepare to make observations from that very particular spot on this earth—the North Pole. I suppose that eternal ice and snow abide there. I don’t think it would be a pleasant residence. However, we shall arrange to arrive on Midsummer Day, prepared to make a year’s sojourn. The first question to be settled is the erection of the hut. In a cold country it is important to give the right aspect, and we are in the habit of saying that a southerly aspect is the best and warmest, while the north and the east are suggestive only of chills and discomfort. But what is a southerly aspect at the North Pole, or, rather, what is not a southerly aspect? Whatever way we look from the North Pole we are facing due south. There is no such thing as east or west; every way is the southward way. This is truly an odd part of the earth. The only other locality at all resembling it would be the South Pole, from which all directions would be north.
The sun would be moving all through the day in a fashion utterly unlike its behavior in our latitudes. There would, of course, be no such thing as rising and setting. The sun would, indeed, at first seem neither to go any nearer to the horizon nor to rise any higher above it, but would simply go round and round the sky. Then it would gradually get lower and lower, moving round day after day in a sort of spiral, until at last it would get down so low that it would just graze the horizon, right round which it would circulate till half the sun was below, and then until the whole disk had disappeared. Even though the sun had now vanished, a twilight glow would for some time be continuous. It would seem to come from a source moving round and round below the horizon, then gradually the light would become fainter and fainter until at last the winter of utter and continuous blackness had set in. The first indications of the return of spring would be detected by a feeble glow near the horizon, which would seem to move round and round day after day. Then this glow would pass into a continuous dawn, gradually increasing until the sun’s edge crept into visibility, and the great globe would at last begin to climb the heavens by its continual spiral until midsummer was reached, when the change would go on again as before.
Our first excursion to the country of Star-land has now been taken, and we have naturally commenced by studying that sun to which we owe so much. But we shall have to learn that though our sun is of such vital importance to us, yet, in magnificence and size, he has many rivals among the host of stars.
LECTURE II.
THE MOON.
The Phases of our Attendant, the Moon—The Size of the Moon—How Eclipses are produced—Effect of the Moon’s Distance on its Appearance—A Talk about Telescopes—How the Telescope aids us in Viewing the Moon—Telescopic Views of the Lunar Scenery—On the Origin of the Lunar Craters—The Movements of the Moon—On the Possibility of Life in the Moon.
THE PHASES OF OUR ATTENDANT, THE MOON.
The first day of the week is related to the greatest body in the heavens—the sun—and accordingly we call that day Sun-day. The second day of the week is similarly called after the next most important celestial body—the moon—and though we do not actually say Moon-day, we do say Monday, which is very nearly the same. In French, too, we have lune for moon, and Lundi signifies our Monday. The other days of the week also have names derived from the heavens, but of these we shall speak hereafter. We are now going to talk about the moon.
We can divide the objects in this room into two classes. There are the bright faces in front of me, and there are the bright electric lights above. The electric lights give light, and the faces receive it. I can see both lights and faces; but I see the electric lamps by the light which they themselves give. I see the faces by the illumination which they have received from the electric lights. This is a very simple distinction, but it is a very important one in Star-land. Among all these bodies which glitter in the heavens there are some which shine by their own light, like the lamps. There are others only brilliant by reflected light, like the faces. It seems impossible for us to confuse the brightness of a pleasant face with the beam from a pretty lamp, but it is often not very easy to distinguish in the heavens between a body which shines by its own light and a body which merely shines by some other light reflected from it. I think many people would make great mistakes if asked to point out which objects on the sky were really self-luminous and which objects were merely lighted up by other bodies. Astronomers themselves have been sometimes deceived in this way.