Science Fair Project Encyclopedia
The constellation Lyra (Latin for Lyre) already formed part of Ptolemy's list of 48 constellations and is also one of the 88 modern constellations approved by the IAU. Lyra is not very big but still easy to find because its principal star, Vega, is also a vertex of Summer Triangle asterism.
Here are some of Lyra's brighter stars:
- α Lyr (Vega): with an apparent brightness of 0.03m this is the second brightest star of the northern hemisphere (after Arcturus) and the fifth brightest star all in all; its spectral class is A0 V and it lies at a distance of merely 25.3 ly. Actually it is a multiple star system (5 components). It was the first star to be photographed.
- β Lyr (Sheliak): a group of eclipsing binaries is named after this variable star (3.45m, spectral class B8 II), the Beta-Lyrae-stars.
- γ Lyr (Sulafat): the main star of this multiple star system is of magnitude 3.24m and spectral class B9 III
- δ Lyr: double star consisting of a blue-white star of 6m and a semi-regular red giant varying between 4m and 5m.
- ε Lyr: well known quadruple star, also called "Double Double" because each of the components is in itself yet another double star.
- ζ Lyr: another double star which can be split using binoculars.
- RR Lyr: lent its name to a whole type of pulsating variable stars, the RR Lyrae-stars.
Notable deep sky objects
- M56: a rather loose globular cluster at a distance of approximately 32,900 ly with a diameter of about 85 ly. Its apparent brightness is 8.3m.
- M57: also known as the "Ring Nebula", this is one of the best known of all planetary nebulae (8.8m; age between 6,000 and 8,000 years).
Older maps of the sky show a bird, especially a vulture (Vultur cadens), in this position, since in early times the constellation and its stars, were taken to resemble a one . As such, together with other constellations in the Zodiac sign of Sagittarius (specifically, Cygnus, and Aquila, together with Sagittarius itself), Lyra may be a significant part of the origin of the myth of the Stymphalian Birds, one of The Twelve Labours of Herakles.
By taking into account slightly parallel lines of fainter stars in the centre of the constellation, it appears to resemble a lyre, and consequently lyra gradually shifted from being considered a vulture to being considered a lyre, for an intermediate period being considered a vulture which is holding a lyre. Associated with its identity as a lyre, Lyra was considered to be the lyre used by Orpheus, to produce music that charmed even Hades, which was placed into the stars upon his death.
Lyra in fiction
In the Star Trek fictional universe, Sheliak (ß Lyrae) is the home system of the alien race by the same name, which views humans and other humanoids as inferior (Star Trek: The Next Generation: "The Ensigns of Command").
Lyra is also the name of one of the two protagonists in Philip Pullman's His Dark Materials trilogy. Her full name is Lyra Belacqua, but her surname becomes changed to Silvertongue. She is the daughter of Asriel Belacqua and Marisa Coulter.
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