The Parents' Review
A Monthly Magazine of Home-Training and Culture
"Education is an atmosphere, a discipline, a life."
The Evening Sky-April 15 to May 15.
By Mrs. L.C.D'A. Lipscomb.
New, April 19th; first quarter, April 27th; full, May 4th; last quarter, May 11th.
Mercury is an evening star, very well situated for observation during the first week in May, as it is at its greatest distance in the sky from the Sun on the 6th.
Venus is an evening star also, in Taurus and then in Gemini. On May 7th, Venus and Mercury and in conjunction, i.e., they are on the same meridian, and will be seen quite near to each other, the more northerly one being Mercury.
Mars comes into view this month in Scorpio, near the S.E. horizon. Next month I hope to give a fuller description of him than there is space for in the present number, and he will then be much more distinctly seen, being nearer the meridian.
Saturn is in Leo, N. of Regulus, and to the naked eye looks like any other very bright star, but when seen through a telescope, he presents a very unusual appearance; in fact, he is unique so far as our experience of the universe extends; he therefore, arouses keen interest, and much time is spent in trying to obtain a correct knowledge of this planet. Unfortunately, he is a long way off (881 millions of miles from the Sun), and sometimes he is low down in the sky, near the horizon of northern astronomers, when a clear picture of him cannot be obtained on account of the density of our own atmosphere; sometimes, again, he is so near the Sun that we cannot see him distinctly on account of the bright sunlight. Occasionally, however, we get favourable opportunities of viewing the planet without these obstructions, and then we have a great treat. The thrill that is felt on the first sight of Saturn through a large telescope is a thing never to be forgotten. It is inevitable; although we may know from drawings and photographs what we are going to see, they do not convey the same impression as the thing itself. We notice first of all a round fiery globe with bands across it, especially marked near the equator. Then our attention is attracted to a broad, flat, bright ring surrounding this, which, on closer inspection, turns out to be really two bright rings, and between them and the globe is what looks like a dark gauze veil; finally, in the neighbourhood we can distinguish several satellites, of which there are altogether eight, more than any other planet possesses, so that the Saturnian system is by far the richest in the solar family. To discover the nature of it's phenomena would afford more than ample work for a lifetime.
In looking at the globe of Saturn, we must remember we cannot see the solid or fluid body of the planet itself, only the outline of its gaseous atmosphere, for it has not cooled as much as the earth, being nine times as large, and having a diameter of 71,904 miles. It's ordinary colour is white, but a yellowish white, the belts are of greyish white, while some of the darker belts seem greenish. Although Saturn is much further from the Sun than we are, and takes about twenty-nine and a half of our years to make one of his, he rotates much more quickly, and his day and night are together only ten and a quarter hours long.
The rings which surround the globe are evidently circular, but we always see them oval, whether above or below their plane; when nearly in their plane they look like a single straight line, and when exactly in their plane (i.e., when a line drawn across the rings are extended far enough would pass through the earth's centre) they disappear altogether, except in the largest telescopes. The ring is inclined 27° to the plane of the ecliptic (i.e., if a line drawn across the Sun's path among the stars were produced to the planet Saturn, the ring would make the angle of 27° with that line), and as the rings always turn the same side to space, just as our North Pole always points to the Pole Star, it follows that we sometimes see the N. and sometimes the S. side of the ring, while mid-way between each we see the ring edgeways, and it practically disappears for the ordinary observers. At present we see the S. side of the ring, but it is closing up, and in 1892 the edge will be turned towards the Sun. When we speak of Saturn's Ring, we mean the whole system, but it is divided into three for convenience sake, the outer bright one being known as A, the inner bright one as B, and the dusky one C. There are other sub-divisions, generally known by the names of the astronomers who first observed them. These rings used to be considered solid, then the fluid theory held ground for a time, but the opinion most in favour now is that they are a dense aggregation of small satellites, close together where brightest, and wider apart where more faint. The rings are brighter than the globe, and B is brighter than A, especially near its outer edge, that being the most brilliant part of the Saturnian system, but at its inner edge it shades off into C so gradually as to make the divisions between them almost imperceptible at times. A has several breaks in it apparently, though they are not always visible.
Seven of the eight satellites are almost in the plane of the planet's equator, so that they are always visible to the inhabitants of both hemispheres (should such exist) except when eclipsed by Saturn's shadow. The said inhabitants must possess a magnificent sky, the rings forming splendid arches across the heavens. The nearest satellite, Mimas, can be seen to move with great rapidity, as in two minutes it moves over a space equal to the width of the Moon as seen from the earth, but it is small in size, being only 1000 miles in diameter. From Saturn the Sun would appear to be scarcely more than a third of the size we see him, on account of the distance being so much greater. Saturn was supposed to be the outermost member of the Solar system until about a hundred years ago, and on account of his comparatively slow and lagging pace, was chosen by the ancients as the symbol for lead.
Aquila is recognized by its three stars in a line almost due north and south, the centre one, Altair, being the brightest.
Auriga, in the fanciful delineations of the ancients, is represented as a charioteer holding a goat in his arm, in the body of which is a star of the first magnitude, Capella (goat) considered by some astronomers to be the brightest star in the northern sky, though others place it second to Sirius.
Canes Venatici are hunting dogs supposed to be held in a leash by Bootes, and are chasing Ursa Major round the Pole. They contain only one prominent star, but several fine nebulae. One of these is especially interesting. It generally, in even good telescopes, looks like two very uneven nebulae nearly touching one another, in the finest telescopes, however, it is seen to be composed of wreaths of stars combined in a wonderful spiral form.
Coma Berenice.--A collection of stars so small, that at a greater distance it would look like a nebula. In the ancient mythology, Berenice had vowed her hair to the goddess Venus; but Jupiter carried it away from the temple in which it was deposited, and made it into a constellation.
Cygnus.--One of these stars is most interesting to us, because being a double one, it was the first of all the host of heaven to have the hitherto immeasurable distance between it and the earth measured, and yet it is so far off that the numbers representing the gulf between convey no idea to our minds. Perhaps some little impression as to its distance may be gathered from remembering that the light from the Sun (nearly ninety-three millions of miles away) reaches us in eight minutes, while that from sixty-one Cygni takes nearly six years to travel to us. To think of it is fatiguing!
Gemini is very low down and difficult to see, but with a low horizon Castor and Pollux can still be made out.
Hydra is a long sinuous constellation, containing nothing of interest to the naked eye. Its head is just under Cancer, a bright star nearly south of Regulus marks its heart, and its tail extends past Crater and Corvus, touching both, until it ends between Virgo and Centaurus.
Scorpio,--Antares is a fiery red star, but it is too low down in the horizon to get much attention from the norther observers. It has a small green attendant of the seventh magnitude. Halfway between the two brightest stars in this constellation is a nebula, in the middle of which suddenly blazed forth in the middle of May, 1860, a bright star, which had almost faded by June 16th, and has never distinctly reappeared. It may form part of the nebula itself, or be in a line between it and the Earth.
The Milky Way makes a circle round the heavens, and sometimes consists of a broad band, while at others it is divided into two narrower ones. This month it appears stretching across the sky from N. to S.E.
Typed by Janice Fuentes, Sept 2015
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