(Encyclopedia) weight, measure of the force of gravity on a body (see gravitation). Since the weights of different bodies at the same location are proportional to their masses, weight is often used…
The Milky Way, the galaxy containing our solar system, is about 100,000 light-years in diameter and about 10,000 light-years thick. Aphelion: see Orbit.
Apogee: see Orbit.
Black hole: the…
(Encyclopedia) Mercury, in astronomy, nearest planet to the sun, at a mean distance of 36 million mi (58 million km); its period of revolution is 88 days. Mercury passes through phases similar to…
Apollo 11July 20 marks the anniversary of man's first walk on the moon by Ricco Villanueva Siasoco How many movies, songs, anecdotes—even clichés—have sprung from humanity's first landing on the…
by Mark Hughes Since its inception in 1958, NASA has built several lines of spaceships that made space exploration reality rather than a dream limited to science fiction, as well…
Feast of the Trumpets remembers world's creation
by David Johnson
Rosh Hashanah begins September 13, 2015 Related Links Lost Tribes of Israel Branches of Judaism Yom Kippur…
(Encyclopedia) Grimaldi, Francesco MariaGrimaldi, Francesco Mariafränchāsˈkō märēˈä grēmälˈdē [key], 1618?–1663, Italian physicist and mathematician. A Jesuit and professor at Bologna, he studied in…
(Encyclopedia) Bouguer, PierreBouguer, Pierrepyĕr b&oomacr;gĕrˈ [key], 1698–1758, French mathematician and hydrographer. He made some of the first photometric measurements, calculating the…
(Encyclopedia) Halley, EdmondHalley, Edmondhălˈē, hôˈlē [key], 1656–1742, English astronomer and mathematician. He is particularly noted as the first astronomer to predict the return of a comet and…
(Encyclopedia) Eris, in astronomy, the largest known dwarf planet. Eris, whose highly eccentric elliptical orbit ranges from 38 AU to 97 AU and is inclined more than 44°, is the largest known object…
