The heavens above: a popular handbook of astronomy (1882)
Gillet, J. A. (Joseph Anthony), 1837-1908 · New York, Chicago, Potter, Ainsworth, & Co. · leaf 111
on.—The sidereal period of the moon is the time it takes her topass around from a star to that star again, or the time it takes her to makea complete revolictionaround the earth.This is a periodof about twenty-sevendays and a third. Itis sometimes calledtlie sidereal month. The synodical peri-od of… … Fig. 108.
Astronomy
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