AQUILA

aquila, in astronomy, the "eagle," sometimes named the "vulture," a constellation of the northern hemisphere, mentioned by eudoxus (4th cent. b.c.) and aratus (3rd cent. b.c.). ptolemy catalogued nineteen stars jointly in this constellation and in the constellation _antinous_, which was named in the reign of the emperor hadrian (a.d. 117-138), but sometimes, and wrongly, attributed to tycho brahe, who catalogued twelve stars in aquila and seven in antinous; hevelius determined twenty-three stars in the first, and nineteen in the second. the most brilliant star of this constellation, [alpha]-_aquilae_ or altair, has a parallax of 0.23", and consequently is about eight times as bright as the sun; [eta]-_aquilae_ is a short-period variable, while _nova aquilae_ is a "temporary" or "new" star, discovered by mrs fleming of harvard in 1899.