The Chautauquan, Vol. 04, July 1884, No. 10

by Chautauqua Literary and Scientific Circle; Chautauqua Institution

FOR JULY.

THE SUN.

We now enter upon what is usually called the “heated term,” in earnest. The “Dog Days” are upon us, that is, we say they are; but the statement is a somewhat doubtful one. We have the story that the ancients regarded the Dog Star, Sirius, in the constellation Canis Major, as the source of “unnumbered woes,” because it rose a short time before the sun about the season of their year that the hot weather set in, and diseases incident to their climate more than usually prevailed. It is said that they estimated this period as continuing for the space of forty consecutive days, beginning twenty days before, and continuing twenty days after what was called the heliacal (that is, rising just long enough before the sun to be visible) rising of the Dog Star. Now, the difficulty we moderns find in fixing the limits of these days is this: The heliacal rising of the star for any one place can readily be found; but when determined for one place, it would not suit for another in a different latitude. Besides, the right ascension of Sirius, on account of the precession of the equinoxes, is constantly increasing, and hence for the same place these days fall later each year, in the course of time occurring even in mid-winter. Almanac makers, when they notice them at all, seem to take the liberty of treating them to suit their own convenience. For example, one of this year’s publications announces that “Dog Days” begin on the 21st of July, and end on the 30th of August, making, as we see by including one extreme date, altogether the forty days claimed by the ancients. But in this latitude, on the former date, the star rises at 5:43 a. m., one hour and five minutes after, and on the latter date at 3:06 a. m., two hours and twenty minutes before sunrise. Others fix the time from July 3rd to August 11th (forty days), without any respect to the rising of Sirius, which on the former date appears above our horizon at 6:51 a. m., or two hours and seventeen minutes after, and on the latter date at 4:18 a. m., forty-nine minutes before sunrise. Others, again, making an effort, we presume, to adapt them to our climate, regard them as continuing only thirty-two days, namely, from July 24th to August 24th. Taking it all in all, we may as well leave them to the Egyptians and Ethiopians, among whom the ideas in regard to them seem to have originated, as a superstition of the past ages, taking our “heated term” at its usual time, July and August, and throwing our “Dog Days,” as some do physic, “to the dogs.”

Whether we account for it by the extreme heat or not, it is nevertheless a fact that the sun lags along behind our clocks during this entire month; on the 1st, not reaching the meridian till 12:03:41 p. m.; on the 15th till 12:05:44 p. m., and on the 30th till six minutes and nine seconds after noon. The time of the sun’s rising on the 1st, 15th and 30th, is 4:33, 4:43 and 4:56 a. m.; and the time of setting on the same dates is 7:34, 7:29 and 7:17 p. m., respectively. The 30th day of this month will be about forty minutes shorter than the 1st, the latter being fifteen hours one minute, and the former fourteen hours and twenty-one minutes in length. The time from daybreak to the end of twilight is, on the 1st, 19 hours 24 minutes. Sun is due west on the 30th at 5:29 p. m. Its greatest elevation above the horizon in latitude 41° 30′, is 71° 33⅔′.

THE MOON

Exhibits the following phases: Full moon, 5:02 a. m. on the 8th; last quarter, 4:30 p. m. on the 15th; new moon, 7:46 a. m. on the 22nd; first quarter on the 29th, at 4:53 p. m. On the 1st it sets at 12:11 a. m., and on the 30th, at 11:51 p. m. On the 15th, rises at 11:32 p. m. On the 4th, at 7:54 a. m., and again on the 31st at 11:00 p. m. it is at its maximum distance from the earth. On the 20th, at 1:36 a. m. is nearest the earth. Its greatest elevation, equal 67° 13⅔′, occurs on the 19th; and its least elevation, amounting to 29° 42⅔′ on the 5th.

MERCURY.

This planet will be morning star till the 13th, after which it will be evening star till the end of the month. It rises on the 1st at 3:41 a. m.; sets on the 15th at 7:41 p. m., and on the 30th at 8:07 p. m., on which latter date it is possibly visible to the naked eye. Its motion during the month is direct, and amounts to 62° 30′ 31.5″. On the 17th at 6:00 a. m. it is nearest the sun; on the 12th at 1:00 a. m., 6° 20′ north of Venus; on the same date, at midnight, is in superior conjunction with the sun; that is, it is in a line with the earth and sun, and in the order, Earth, Sun, Mercury; on the 23rd, at 3:00 a. m., 1° 10′ north of Jupiter; and on the 23rd, at 7:05 a. m., 6° 30′ north of the moon. Diameter decreases from 5.6″ to 5.4″.

VENUS.

A view of Venus during this month through a telescope of moderate power would be an interesting sight, since she now presents the appearance of our moon in its first or last quarter, and thus seems quite different from the simple star that is visible to the naked eye. She will be evening star till the 11th, at which time she reaches her inferior conjunction, that is, reaches a point directly between the earth and the sun; after which she will be morning star, not only to the end of this month, but for several successive months. Of course, for a number of days both before and after conjunction, she will, on account of her proximity to the sun, be invisible. We shall miss her “beaming countenance,” but we know that she will appear again. On the 1st she sets at 8:14 p. m., and rises on the 15th at 4:38 a. m., and on the 30th at 3:17 a. m. On the 21st at 6:28 a. m. she is 1° 11′ south of the moon; and on the 29th at 11:00 a. m., farthest from the sun.

MARS

Has from the 1st to 30th a direct motion of 15° 36′ 32″, and although much reduced in apparent diameter, is still quite a prominent object in the evening sky, following westward in the wake of Jupiter. His diameter decreases from 5.6″ to 5.2″. He rises in the forenoon, and sets as follows, in the evening: On the 1st at 10:47; on the 15th at 10:11; and on the 30th at 9:31. On the 26th at 5:04 p. m. he is 2° 5′ north of the moon.

JUPITER

Will be evening star throughout the entire month, though at its close approaching so near the sun as to be scarcely visible. He sets at the following times: On the 1st at 9:08; on the 15th at 8:22; and on the 30th at 7:33 p. m. His motion is direct, and amounts from the 1st to the 30th, to 6° 17′ 55″. Diameter decreases from 30.2″ to 29.6″. On the 23rd, at 3:00 a. m. is 1° 10′ south of Mercury; and on the same day at 6:34 a. m. is 5° 21′ north of the moon.

SATURN.

This planet is now one of our morning stars, rising on the 1st at 3:06, on the 15th at 2:17, and on the 30th at 1:25 a. m. Motion direct, amounting to 3° 32′ 30¾″. Diameter increases from 15.6″ to 16.2″. On the 19th, at 1:01 p. m. is 3° 2′ north of the moon.

URANUS,

Whose direct motion during the month is estimated at 1° 3′ 26″, continues its role as evening star, setting at the following times: On the 1st at 11:10; on the 15th at 10:16; and on the 30th at 9:17 p. m. On the date last named, Beta Virginis will be only two minutes south of and will set at the same time as the planet. On the 19th, at 2:00 p. m., Uranus will be eleven minutes north of Mars; and on the 26th, at 9:57 a. m. will be 2° 43′ north of the moon.

NEPTUNE

Scarcely affords this month material for comment. Its diameter at present appears to be 2.6″. Its motion is 40′ 35″, and is direct. On the 1st it rises at 1:44 a. m.; on the 15th at 12:49 a. m.; and on the 30th at 11:45 p. m. At 5:27 p. m., on the 17th, it will be 1° 11′ north of the moon.

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