Page:Popular Astronomy - Airy - 1881.djvu/86

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72
POPULAR ASTRONOMY

low. In summer, the sun is a long time above the horizon, and a short time below: in winter he is a short time above the horizon, and a long time below. In summer, the sun rises north of the east point, and sets north of the west point; in winter he rises south of the east point, and sets south of the west point. These observations are all explained by saying that in summer the sun is nearer to the North Pole, and in winter nearer to the South Pole. And this you can verify without the smallest trouble, from your own observations.

Now, I will offer a few words in regard to the stars visible at different times of the year. I will suppose that at eleven o'clock at night you look out to see what stars are on the meridian. On the first of January if you look out at eleven o'clock at night, you will see the grand constellation Orion on the meridian; Aldebaran and Pleiades are west of the meridian. The bright star Sirius has not yet come to the meridian. I now suppose that you look out, in the same way, on the first of February, taking the same hour. On the first of February, at eleven o'clock at night, you see that Aldebaran and the Pleiades are setting in the west; that Orion has got a good way to the west; and that Sirius has passed the meridian a little way. There are three conspicuous stars near the meridian, well known by everybody who is accustomed to look at the constellations; namely, the pair of twins, Castor and Pollux, and Procyon, or the Little Dog. On the first of March, at eleven o'clock at night, you again look out; Castor, Pollux, Sirius, and the Dog Star, have then gone away to the west; Orion is now setting; and we then have the stars of the constellation Leo, which is a bright constellation, approaching the