Mattison, Hiram, 1811-1868 · New York, Huntington and Savage, Mason and Law · leaf 124
therefore, may we expect Eclipses of the Sun ?Whenever the Moon is within 17° of either Node at the time of her change. 540. What is meant by the Umbra of the Earth and Moon ? It is the dark shadow cast in a direction opposite theSun. [ Umbra is a Latin word, signifying a shade or shadow.] 541.… … [1. In this cut, the Earths umbra and penumbra will be readily found by the let-tering, while A is the umbra and B B the penumbra of the Moon. The latter is morebroad than it should be, owing to the nearness of the Sun in the cut, as it neverextends to much over half the Earths diameter. 2. The…
Astronomy
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