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THE GUIDE TO NATURE 



frequently, especially as all of our plan- 

 ets are so bright that the faint stars 

 seem to disappear as the planet draws 

 near them. The last observation of 

 this nature to be reported was an oc- 

 culation on the 13th of last August of 

 a seventh magnitude star by the planet 

 Jupiter, of which several observations 

 and several photographs were taken. 

 In this case the brightness of the star 

 diminished as it drew near the edge of 

 the planet, but what is of especial in- 

 terest is that when apparently touching 

 the edge it disappeared instantly, prob- 

 ably because its light suddenly became 

 hidden by an impenetrable cloud of va- 

 por. Usually the disappearance is 

 gradual, the star "hanging on the 

 limb," as astronomers say, until finally 

 the interposed vapors become so dense 

 that it is no longer visible. 



THE PLANETS IN AUGUST. 



Mercury, which reached its greatest 

 distance east of the sun on July 24, 

 runs rapidly westward throughout the 

 month, passing the sun and entering 

 the morning sky on August 22, but 

 not reaching western elongation until 

 September 7. It may be seen with dif- 

 ficulty low in the northwest just after 

 sunset, toward the beginning of the 

 month, and in the morning sky in the 

 northeast toward the end of the month 

 just before sunrise. 



Venus is also too near the sun to be 

 easily observed. It sets in the north- 

 west only 32 minutes after sunset on 

 August 1, but this time is increased to 

 50 minutes by August 31, when it may 

 be detected shining out in the north- 

 west, very near the ground, just after 

 sunset. 



Mars, though continuing its rapid 

 eastward motion across Leo and into 

 Virgo, is being so rapidly overtaken 

 by the sun that it has now moved just 

 beyond the borders of our monthly 

 map. On August 27 it will pass very 

 close to the bright yellowish star Beta 

 Virginis. If the observer will turn due 

 west at about eight o'clock on this 

 evening he will see these two bright 

 objects only a short way above the 

 ground and so near together that they 

 can be distinguished only with diffi- 

 culty with the naked eye. In a pair of 

 opera glasses or in a small telescope, 

 however, they will form an interesting 

 figure, the brighter and far redder Mars 



lying a very little distance to the south 

 of the yellow star. 



Jupiter will at once attract attention, 

 as it shines out so brightly, a little 

 toward the west of the south point, 

 near the center of the striking summer 

 constellation of the Scorpion. It is 

 still in excellent position for observa- 

 tion, and with its bright moons and its 

 banded surface is a magnificent sight. 



Saturn may be seen well up from the 

 ground in the east, almost exactly mid- 

 way between the beautiful groups of 



Figure 3. Showing the position of the meteor swarm 

 through which the earth passes on August 10, 1913. 



the Hyades and the Pleiades at I 

 o'clock in the morning. The rings are 

 now well widened out and the planet 

 presents a beautiful sight in a small 

 telescope. This part of the morning sky 

 is now so attractive and will so well 

 repay observation on account of the 

 presence of Saturn, the occurrence of 

 the August meteors and the close pas- 

 sage of the moon to the Pleiades, on 

 the night of August 6, that we add this 

 month a chart of it (Fig. 2). 



Uranus is moving slowly west and 

 south in the constellation Capricornus. 



Neptune is too close to the sun to be 

 observed during this month. 



