CONSTELLATIONS NEAR THE POLE STAR.
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Supposing the axis of the earth were quite upright, straight up and down in regard to the plane at which the earth goes round the sun, then we should always see the same set of stars from the Northern and the same set of stars from the Southern Hemispheres all the year round. But as the axis is tilted slightly, we can, during our nights in the winter in the Northern Hemisphere, see more of the sky to the south than we can in the summer; and in the Southern Hemisphere just the reverse is the case, far more stars to the north can be seen in the winter than in the summer. But always, whether it is winter or summer, there is one fixed point in each hemisphere round which all the other stars seem to swing, and this is the point immediately over the North or the South Poles. There is, luckily, a bright star almost at the point at which the North Pole would seem to strike the sky were it infinitely lengthened. This is not one of the brightest stars in the sky, but quite bright enough to serve the purpose, and if we stand with our faces towards it, we can be sure we are looking due north. How can we discover this star for ourselves in the sky? Go out on any starlight night when the sky is clear, and see if you can find a very conspicuous set of seven stars called the Great Bear. I shall not describe the Great Bear, because every child ought to know it already, and if they don't, they can ask the first grown-up person they meet, and they will certainly be told. (See [map].)

Having found the Great Bear, you have only to draw an imaginary line between the two last stars forming the square on the side away from the tail, and carry it on about three times as far as the distance between those two stars, and you will come straight to the Pole Star. The two stars in the Great Bear which help one to find it are called the Pointers, because they point to it.

The Great Bear is one of the constellations known from the oldest times; it is also sometimes called Charles's Wain, the Dipper, or the Plough. It is always easily seen in England, and seems to swing round the Pole Star as if held by an invisible rope tied to the Pointers. Besides the Great Bear there is, not far from it, the Little Bear, which is really very like it, only smaller and harder to find. The Pole Star is the last star in its tail; from it two small stars lead away parallel to the Great Bear, and they bring the eye to a small pair which form one side of a square just like that in the Great Bear. But the whole of the Little Bear is turned the opposite way from the Great Bear, and the tail points in the opposite direction. And when you come to think of it, it is very ridiculous to have called these groups Bears at all, or to talk about tails, for bears have no tails! So it would have been better to have called them foxes or dogs, or almost any other animal rather than bears.

Now, if you look at the sky on the opposite side of the Pole Star from the Great Bear, you will see a clearly marked capital W made up of five or six bright stars. This is called Cassiopeia, or the Lady's Chair.

In looking at Cassiopeia you cannot help noticing that there is a zone or broad band of very many stars, some exceedingly small, which apparently runs right across the sky like a ragged hoop, and Cassiopeia seems to be set in or on it. This band is called the Milky Way, and crosses not only our northern sky, but the southern sky too, thus making a broad girdle round the whole universe. It is very wonderful, and no one has yet been able to explain it. The belt is not uniform and even, but it is here and there broken up into streamers and chips, having the same appearance as a piece of ribbon which has been snipped about by scissors in pure mischief; or it may be compared to a great river broken up into many channels by rocks and obstacles in its course.

The Milky Way is mainly made up of thousands and thousands of small stars, and many more are revealed by the telescope; but, as we see in Cassiopeia, there are large bright stars in it too, though, of course, these may be infinitely nearer to us, and may only appear to us to be in the Milky Way because they are between us and it.

Now, besides the few constellations that I have mentioned, there are numbers of others, some of which are difficult to discover, as they contain no bright stars. But there are certain constellations which every one should know, because in them may be found some of the brightest stars, those of the first magnitude. Magnitude means size, and it is really absurd for us to say a star is of the first magnitude simply because it appears to us to be large, for, as I have explained already, a small star comparatively near to us might appear larger than a greater one further away. But the word 'magnitude' was used when men really thought stars were large or small according to their appearance, and so it is used to this day. They called the biggest and brightest first magnitude stars. Of these there are not many, only some twenty, in all the sky. The next brightest—about the brightness of the Pole Star and the stars in the Great Bear—are of the second magnitude, and so on, each magnitude containing stars less and less bright. When we come to stars of the sixth magnitude we have reached the limit of our sight, for seventh magnitude stars can only be seen with a telescope. Now that we understand what is meant by the magnitude, we can go back to the constellations and try to find some more.

If you draw an imaginary line across the two stars forming the backbone of the Bear, starting from the end nearest the tail, and continue it onward for a good distance, you will come to a very bright star called Capella, which you will know, because near it are three little ones in a triangle. Now, Capella means a goat, so the small ones are called the kids. In winter Capella gets high up into the sky, and then there is to be seen below her a little cluster called the Pleiades. There is nothing else like this in the whole sky. It is formed of six stars, as it appears to persons of ordinary sight, and these stars are of the sixth magnitude, the lowest that can be seen by the naked eye. But though small, they are set so close together, and appear so brilliant, twinkling like diamonds, that they are one of the most noticeable objects in the heavens. A legend tells that there were once seven stars in the Pleiades clearly visible, and that one has now disappeared. This is sometimes spoken of as 'the lost Pleiad,' but there does not seem to be any foundation for the story. In old days people attached particular holiness or luck to the number seven, and possibly, when they found that there were only six stars in this wonderful group, they invented the story about the seventh.