Astronomy with the naked eye; a new geography of the heavens, with descriptions and charts of constellations, stars, and planets

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1908 edition. Excerpt : …

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1908 edition. Excerpt : . . . THE ZODIACAL LIGHT THIS mysterious phenomenon is not, strictly speaking, a stellar object, although it is unquestionaably connected with a star–our own sun. Like the constellations and the Milky Way, it has long attracted a great deal of attention, although it is too indefinite to have any mythological associations, and even yet its nature is not well understood. The general opinion at present is that the Zodiacal Light is a faint extension of the sun’s corona. It is generally described as a cone – shaped or lenticular light, rising above the western horizon after sunset and above the eastern horizon before sunrise, but not to be seen at all seasons. It is especially a naked-eye object, for it is too diffuse to be observed with a telescope, and attempts to photograph it are not very successful. The light lies in, or very near, the plane of the ecliptic, and consequently is best seen when the ecliptic makes the steepest angle with the horizon. For our latitudes this occurs in the evening during February, March, and April, and in the morning during September and October. It can be traced in a clear sky, and in the absence of moonlight to a distance of about sixty degrees from the sun. Of course, it cannot be seen while the sun is above the horizon, and not immediately after sunset or before sunrise. It is sometimes confounded with twilight, but its distinct nature may be immediately recognized from its shape. Naturally it is best seen in equatorial regions, and Lieutenant Jones, who made a special study of it many years ago, traced it past the zenith, and believed that he could follow it completely across the sky. It ought, indeed, to be thus visible, under favorable circumstances, if it be what it is supposed to be–a nebulous envelope. . .

CCD Astronomy

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