The geography of the heavens and classbook of astronomy; (1863)
Burritt, Elijah H. (Elijah Hinsdale), 1794-1838, Mattison, Hiram, 1811-1868, Whitall, Henry, 1819-1887? Celestial planisphere. [from old catalog] · New York, Mason brothers; Boston, Mason & Hamlin; [etc., etc.] · leaf 224
ry? Why?449. Average length of the Moons umbra? Does it vary ? Why? Greatest diameterat the Earths surface? Of penumbra ? What is an appulse? 450. A partialeclipse? A total? A central? Are all central eclipses total? Why not? What calledthen? WThy? 222 ASTRONOMY. whole disc of the Sun. In that… … 451. It has already been shown that the apparent magni-tudes of bodies vary as their distances vary ; and as both theEarth and Moon revolve in elliptical orbits, it follows that theMoon aud Sun must both vary in their respective apparent mag-nitudes. Hence some central eclipses of the Sun are…
Constellations · Stars
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![An illustration from Sidereus nuncius : magna, longeque admirabilia spectacula pandens, suspiciendaque proponens vnicuique, praesertim verò philosophis, atq[ue] astronomis, quae à Galileo Galileo ... perspicilli nuper à se reperti beneficio sunt obseruata in lunae facie, fixis innumeris, lacteo circulo, stellis nebulosis, apprime verò in quatuor planetis circa Iouis stellam disparibus interuallis, atque periodis, celeritate mirabili circumuolutis; quos, nemini in hanc vsque diem cognitos, nouissimè author depraehendit primus; atque Medicea sidera nuncupandos decreuit (1610)](https://img.insideoutlibrary.com/img/200/ia-sidereusnunciusm00gali-25-8.webp)
