1911 Encyclopædia Britannica/Lyra
|←Lyons, Councils of||1911 Encyclopædia Britannica, Volume 17
|See also Lyra on Wikipedia, and our 1911 Encyclopædia Britannica disclaimer.|
LYRA (“The Harp”), in astronomy, a constellation in the northern hemisphere, mentioned by Eudoxus (4th century B.C.) and Aratus (3rd century B.C.). Ptolemy catalogued 10 stars in this constellation; Tycho Brahe 11 and Hevelius 17. α Lyrae or Vega, is the second brightest star in the northern hemisphere, and notable for the whiteness of its light, which is about 100 times that of the sun. The name “vega” is a remnant of an Arabic phrase meaning “falling eagle,” “Altair,” or a Aquilae, is the similar remnant of “flying eagle.” ε Lyrae is a multiple star, separated by the naked eye or by a small telescope into two stars; these are each resolved into two stars by a 3" telescope, while a more powerful instrument (4") reveals three smaller stars between the two pairs. β Lyrae and R. Lyrae are short period variables. There is the famous ring or annular nebula, M. 57 Lyrae, in the middle of which is a very faint star, which is readily revealed by photography; and also the meteoric swarm named the Lyrids, which appear in April and have their radiant in this constellation (see Meteor).