The Parents' Review
A Monthly Magazine of Home-Training and Culture
"Education is an atmosphere, a discipline, a life."
The Evening Sky.
THE MOON. Last quarter, 5th; new, 13th; first quarter, 21st; full, 27th.
There are two interesting occultations during the month especially that of Neptune, which occurs on the 2nd, and lasts from 9.46 to 10.42 p.m.
On the 27th, ξ Ceti, of magnitude 4½, is occulted from 7.22 to 8.21 p.m.
THE PLANETS. Venus is at her greatest brilliancy towards the end of the month, when she sets before six o'clock. This planet presents great difficulties in her definition, firstly on account of her own brightness, and secondly by reason of her proximity to the Sun. She is about as large as the Earth, her equatorial diameter being only 300 miles less.
Like the Moon and Mercury, she exhibits different phases during her journey round the Sun, being full when she passes beyond the Sun, or in astronomical parlance, is in superior conjunction, while shortly before and after inferior conjunction (when she is between us and the Sun), she appears as a crescent, and then also is largest on account of her comparative nearness to the Earth. When at greatest elongation, or furthest away from the Sun in the sky from our point of view, she is like the Moon in quadrature, just half visible.
Very little is known about Venus's actual condition. We may conclude she is enveloped by a vaporous atmosphere, as all observations tend to prove it. She also seems to possess mountains, for the line of separation between the shadow and the illuminated ated portion of the planet is unevenly notched and indented, but if so, they must be much more lofty than any on the earth, for some have been calculated to be nearly twenty-seven miles high, i.e., five times as high as the loftiest peaks of the Himalayas.
Until lately it has been accepted that her period of revolution on her own axis was similar to that of the Earth, about 23 hours 21 minutes 8 seconds, but recent investigations tend to show that, like the moon, her revolution on her axis corresponds to that in her orbit, she turning always the same side to the Sun. This, however, remains a moot point.
In ancient days the evening star was called Hesperus or Venus, and the morning star Phosphorus or Lucifer, but it gradually dawned upon men's minds that the two were never visible together, and they noticed that Venus sank lower and nearer to the Sun, until she was lost in his rays, and that after a short time Lucifer first appeared in the mornings close to the Sun, gradually extending his distance from him until he too retraced his steps, to reappear after an interval as Venus. Thus it became apparent they were one and the same planet.
Mars is in Sagittarius, and sets about 9 p.m. Jupiter is in Capricornus, and sets about 11 p.m. He is, however, too near the horizon to be included in the map for this month.
THE CONSTELLATIONS. Cassiopeia, or the Lady in the Chair, is easily found at all times, as she is on the opposite side of the Pole Star to Ursa Major, and her principal stars resemble rather an uneven W. This group is above the horizon throughout its whole journey round the Pole, and at present is on the meridian and just over-head. In the ancient mythology, Cassiopeia is the queen of Cepheus, and in the constellation she is represented as seated on a large chair or throne, from which she is issuing her edicts.
In November, 1572, a great new star appeared in Cassiopeia, so bright that it was visible at noonday, but by the end of sixteen months it had faded to utter extinction. As a similar burst of light seems to have taken place in 945 and 1264, it is just possi-ble it is of periodical occurrence, and if so, is about due at the Present time. Tycho Brahe ascribed the appearance to a sudden concentration of nebulous material in the Milky Way.
Andromeda. - In this constellation is a great Nebula, elliptic In shape, occupying space in the sky equal in length to five, and in breadth to two diameters of the full Moon. It has a bright central condensation sufficient to make it visible to the naked eye, and contains two curious black streaks or longitudinal vacuities running nearly parallel to the longer axis of the oval on the South side.
What makes it particularly interesting to us is the marvellous change it underwent in 1885, when we remember there was great excitement about Nova Andromeda. On August 17th, a bright star of the 9th magnitude suddenly appeared in it, near its centre, which, by September 1st, had risen to the 7th magnitude, after which it rapidly fell off in brilliancy, and in March of the following year was of the 16th magnitude, visible only in large telescopes. When it first began to fade, its sharply-defined ruddy disc was plainly outlined against the hazy background of the nebula, which was greenish-white in colour. It has a continuous spectrum, therefore is solid or fluid, but not gaseous.
Andromeda is represented with her hands in chains, waiting for Perseus to release her. She is sometimes called the guard of Cassiopeia, and can always be found on the other side of that constellation to the North Pole.
Pisces is one of the groups of the Zodiac, and is now on the meridian, but it is uninteresting to the naked eye.
Cetus contains one of the greatest wonders of the heavens in its star ω Ceti, which also has the name of Mira, or the Wonderful. It is a variable star, with a period of 331 days 8 hours. For about five months it is quite invisible, then when it appears it increases until it is nearly of the second magnitude, but its maximum of brilliancy is not always the same. It remains at its brightest for a fortnight, then decreases for two months, and again remains invisible for five months, taking three months to increase once more. It was at its maximum this year at the beginning of July. Cetus is the largest constellation in the heavens.
METEORS. During October, from the 19th to the 25th, there will be a rich and distinct shower of shooting stars, known as the Orionids, because they seem to emanate from the constellation of Orion.
Typed by happi, Apr 2016
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