Aquila is a constellation. Its name is Latin for 'eagle' and it is commonly represented as such. It lies roughly at the celestial equator. The alpha star, Altair, is a vertex of the Summer Triangle asterism. Aquila was one of the 48 constellations described by the 2nd century astronomer Ptolemy. It had been earlier mentioned by Eudoxus in the 4th century BC and Aratus in the 3rd century BC. It is now one of the 88 constellations defined by the International Astronomical Union. The constellation was also known as Vultur volans (the flying vulture) to the Romans, not to be confused with Vultur cadens which was their name for Lyra. Ptolemy catalogued nineteen stars jointly in this...