ByProf.M. B. GOFF.
The source of all our light and heat, although about three millions of miles nearer to us on the 2d of January than it was on the 3d of July last, affords neither the same quantity of light nor heat; and for two reasons: 1. His rays fall on us more obliquely. 2. He does not remain so long above our horizon. On the 1st he rises at 7:24 a. m. and sets at 4:44 p. m., making our day only nine hours and twenty minutes long; and on the 31st rises at 7:11 a. m. and sets at 5:16 p. m., giving us ten hours and five minutes for a day’s length, an increase of forty-five minutes.
Presents the usual phases in order, as follows: First quarter on the 5th, at 4:27 p. m.; full moon on the 12th, at 10:19 a. m.; last quarter on the 20th, at 12:15 a. m.; and new moon on the 27th, at 11:53 p. m., Washington mean time, which is 8 minutes 12.09 seconds slower than “Eastern time,” or the time of the 75th meridian west of Greenwich. The moon is nearest the earth at 11:36 a. m. on the 9th; and most distant from the earth at 6:12 a. m. on the 21st. On the 10th she reaches her greatest elevation, which is 67° 42′ above the horizon in latitude 41° 30′ north.
Will be distinctly visible every evening from the first to the thirteenth of the month, setting at 6:06 p. m. on the evening of the former date, and at very nearly the same hour on the latter date. From the 1st to the 11th its motion is from west to east; on the 11th it is said to be stationary; however, it is actually moving in its orbit about thirty thousand miles per hour; but is approaching us in an almost direct line, and thusseemsto be at a stand still. On the same day, it arrives at its greatest distance east of the sun, 19° 16′, and then starts on its journey west, approaching the earth, and coming directly between it and the sun, that is, reaching its inferior conjunction about 3:00 on the afternoon of the 20th. On the 31st it will be so far west as to rise one hour and fourteen minutes earlier than the sun.
Will be evening star during the month, setting at 6:38 on the evening of the 1st, and at 7:50 p. m. on the 31st. Her motion is direct, amounting, during the month, to 2 hours, 24 minutes, 38 seconds, equal to 36° 9½′ of arc, her diameter increasing from 11.6′ to 12.8′. This planet will delight the vision of star-gazers, not only during January, but several succeeding months.
Will continue his retrograde motion during the month, moving a little more than one minute per day, making in all 35 minutes 37 seconds. He will be quite a prominent object during the entire night, on the evening of the 1st, rising at 7:50, and on the following morning setting at 9:58; and on the 31st rising at 5:08 p. m., and setting at 7:44 the next morning. His diameter at the latter date will be 15″. Can be readily found in the constellationLeo, northwest of the bright star Regulus. At 1:29 p. m. on the 14th he will be 9° 18′ north of the moon.
Will commence the month as a morning star, rising on the 1st at 6:19 in the evening, and setting next morning at 8:45; but on the 13th will change to an evening star, being on this date in opposition to the sun, and rising as the latter sets at about 5:00 p. m. On the 13th, at 2:53 a. m., he will be 5° 41′ north of the moon. On the 31st he will rise at 4:00 p. m., and next morning will set at 6:34. His diameter at same date will be 43.8″. Motion during the month, 16 minutes 12.54 seconds retrograde. The eclipses of this planet’s moons, by the body itself, are sometimes used for the purpose of determining longitude. He will be found in the constellationCancer.
“The father of gods and men,” rises on the 1st at 2:18 p.m.; sets on the 2d at 4:34 a. m., being over 14 hours above the horizon. On the 31st it rises at 12:12 p. m. and sets next morning at 2:32. Has a retrograde motion of 4 minutes 3.61 seconds. On the 9th at 2:14 a. m. it is only 59′ north of the moon. Its diameter is about 18 seconds. Can be found in the constellationTaurus, a little northwest of Aldebaran, the brightest star of the clusterHyades.
Is morning star for the month. On the 1st it rises at 11:08 in the evening; on the 2d at about 10:00 a. m. Although traveling at the rate of over one and one-fourth million miles per hour, it is said to be stationary. As in the case of Mercury, itmoves toward us for the time in an almost straight line, and “is not what it seems.” It has from the 2d to the end of the month a retrograde motion of 21 minutes 15 seconds of arc. Its diameter is 3.8 seconds. On the 31st it rises at 9:07 in the evening.
Will be evening star during the month, rising at 1:35 p. m. on the 1st and at 11:36 a. m. on the 31st, and setting at 3:09 a. m. on the 2d, and at 1:10 a. m. on the 1st of February. On the 8th, at 1:02 a. m., it is 6′ south of the moon. On the 28th, at 3:00 p. m., it is stationary. From the 1st to the 28th its motion will be 12½ seconds of arc retrograde, and from the latter date to the end of the month 8.7 seconds of arc direct. Its diameter equals 1.6 seconds. Will be found in the constellationAries. Neptune is so far away that really little is known in regard to it. Its peculiar interest to us centers in the fact developed in its discovery, namely, that notwithstanding comparatively little is definitely settled in astronomical science, a wonderful degree of exactness has been attained in the computation of the places of the heavenly bodies. In 1820, astronomer Bouvard, of Paris, made a new and improved set of tables which formed the basis of the calculations made on the motions of Jupiter, Saturn and Uranus. In a few years it was found by observations that Uranus failed to occupy the place assigned him by the tables. In twenty-four years the disagreement amounted to two minutes of arc (a slight error, one would think, but not to be overlooked, and easily measured). The discrepancy led Mr. John C. Adams, an English student, in 1843, and M. Leverrier, a Frenchman, in 1845, each without the knowledge of the other, to attempt to reckon the elements of an unknown planet that would cause the disturbance. Adams, in October, 1845, communicated the results of his efforts to Prof. Airy, Astronomer Royal, who, however, for some reason not very clear, failed to make any search in the quarter directed. In 1846, the result of Leverrier’s calculations were published, and bore such a striking similarity to those of Mr. Adams, that Prof. Challis, of Cambridge Observatory, immediately began a very thorough search, and had made considerable progress, when Leverrier in September, 1846, wrote to Dr. Galle, of Berlin Observatory, giving him the elements, and asking him to direct his telescope to a certain portion of the heavens. This the Doctor did, and the result was that on the 23d of September, 1846, the planet afterward called Neptune, was found within a very short distance from the point indicated by both M. Leverrier and Mr. Adams.