A beginner's star-book; an easy guide to the stars and to the astronomical uses of the opera-glass, the field-glass and the telescope . the pole. So wide is the circle whichit makes in its daily revolution that its stars not only dip below the horizon, but are reallyabove it for only about lo hours in the 24. As it is so far from the pole we will face nowtowards the south. On the same evening, November 20th, let us first realize as we facesouthward that we have put the pole at our backs. The east, therefore, will be now atour left; the west will be at our right. At 8 P. M. on November 20th, th
A beginner's star-book; an easy guide to the stars and to the astronomical uses of the opera-glass, the field-glass and the telescope . the pole. So wide is the circle whichit makes in its daily revolution that its stars not only dip below the horizon, but are reallyabove it for only about lo hours in the 24. As it is so far from the pole we will face nowtowards the south. On the same evening, November 20th, let us first realize as we facesouthward that we have put the pole at our backs. The east, therefore, will be now atour left; the west will be at our right. At 8 P. M. on November 20th, the stars of Orion,perhaps the most beautiful of the constellations, begin to appear low down in the easternsky. By 9 oclock these stars will probably be clear of the mists that in Autumn so often lieat the edge of the world; and by 9:30 or 10 they will be well placed for group is now, let us assume, at position A, with the three bright stars that passdiagonally through the great square, pointing upward ;* by 1: 30 A. M. it will reach positionB; by 5 a. m. it will reach position C; by 8 A. m. it will have set. fiA. THREE POSITIONS OF ORION Most of us, however, do not care to watch through a whole night, even to follow themarch of such a constellation as Orion. We will prefer to follow the other method. Re-membering that the stars rise each evening four minutes earlier than on the evening before,we can just as well follow Orion through his march across the sky by looking for him throughthe hours of the early evening at successive dates. We shall need more time than onenight or one week or one month. As Orion comes to position A four minutes earliereach night, so it will be four minutes earlier when he reaches position B; and by 8 P. January we shall find these stars nearer to B than to A. At 8 in February they will bequite at B, and by 8 P. M. in Aisril they will be at C. We shall thus have almost sixmonths in which we shall find Orion conveniently placed for
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Keywords: ., bookcentury1900, bookdecade19, booksubjectastronomy, bookyear1912
