This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1855 Excerpt: ...the meridian once oftener than the Sun. If, instead of comparing the Moon and star, or Sun and star, we compare the Moon and Sun, it is plain that when the lunar month has elapsed, and the Moon and star are again on the same meridian, it will require an additional time for the Moon to overtake the Sun, and pass the ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1855 Excerpt: ...the meridian once oftener than the Sun. If, instead of comparing the Moon and star, or Sun and star, we compare the Moon and Sun, it is plain that when the lunar month has elapsed, and the Moon and star are again on the same meridian, it will require an additional time for the Moon to overtake the Sun, and pass the meridian again in company with him. The interval of time between two successive meridian passages of the Sun and Moon in company is called a Synodic Month, and is found by observation to be equal to 2od I2h I4m 29.87. The Moon is said to be in Conjunction with the Sun when she passes the meridian with the Sun, or has the same right ascension; and since she travels eastward at the rate of 130 10' 55" per day, while the Sun travels eastward at the rate of only 59' 8" per day, she will separate from the Sun at the rate of 120 11' 47" per day. In somewhat more than a week, or seven days, she will be 900 east of the Sun, and is then said to be in Quadrature; when she is 1800 distant from the Sun, she passes the meridian at midnight, and is said to be in Opposition; when she has travelled 2700 east, or is 900 west of the Sun, she is again in quadrature; and so on. The hemisphere of the Moon which is turned towards the Sun is enlightened, and the hemisphere turned from the Sun is dark. In the accompanying figure let E represent the Earth, S the Sun, and a the Moon in conjunction. The dark hemisphere of the Moon is turned towards the Earth in this position, and the Moon is not visible; this condition of the Moon is called New Moon: when the Moon is in opposition at b, the hemisphere enlightened by the Sun is turned towards the Earth, and the Moon appears as a full circle of light; this condition of the Moon is called Full Moon: when, howev...
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