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LYRA
The Harp
Lyra - Celestial Atlas by Alexander Jamieson - 1822
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It is said that Hermes ( Mercury) took the shell of a tortoise, poked holes on two sides of the rim, strung thin strips of cow gut between them, and the lyre, the first ancient form of the harp, was born. The instrument was traded to Apollo in exchange for some cattle, and Apollo ultimately gave it to Orpheus, who became the most skilled and famous musician of the ancient world. His music contained a powerful magic that charmed everyone that heard it. It even charmed the rocks and the trees. Traveling with Jason and the Argonauts in search of the Golden Fleece, his music was even powerful enough to save them all from the song of the Sirens. When Orpheus died, the Muses asked Zeus ( Jupiter) to place the lyre in the sky, to honour the god-like music it produced. It was carried up to the heavens in the beak of a vulture, which is the way it is depicted in many older star maps.
The constellation Lyra contains the fifth brightest star in the sky, Vega, with a magnitude of 0.03. It is one of the closest stars to Earth, only 25.3 light years away, and far outshines any other star anywhere near it, so it is easy to find. Vega is Arabic for vulture. Vega is also the star from which the first communication from extraterrestrial life was received in the famous book and movie by Carl Sagan, Contact.
The second brightest star is Sheliak, Arabic for harp. It has a magnitude of 3.52, and is 882 light years away. The third brightest is Sulafat, Arabic for tortoise, from which the first harp was formed. Sulafat has a magnitude of 3.30, and is 635 light years away.
Lyra contains two Messier objects. The first is M56, a beautiful globular star cluster, 32,900 light years away, and 85 light years in diameter, shown below.
Lyra also contains probably the most accessible and well known planetary nebula in the sky, M57, also known as the Ring Nebula. It is usually one of the first deep sky objects found by amateur telescopes, as it is easy to find, halfway between the stars Sheliak and Sulafat. M57 has a magnitude of 8.8, and is 2,000 light years from Earth. Below you can see the true splendor of the nebula through the eyes of the Hubble Space Telescope.
Scientists have already detected eleven planetary systems in Lyra, and expect to find many more over the next few years, thanks to NASA's Kepler Space Telescope. Launched in March, 2009, it is the most light sensitive telescope ever built, for the sole purpose of discovering exoplanets. To avoid contamination, Kepler is millions of miles away from Earth, in orbit around the Sun. For the next four to six years, Kepler will remain focused on one spot, simultaneously and continuously monitoring the light from the same 100,000 stars, to detect the minute changes caused by a planet transiting (crossing in front of) one of them. A small area between Lyra and Cygnus was chosen for its abundance of stars and its lack of interference from the Sun and other light sources. For more information on the Kepler mission, go to http://kepler.nasa.gov/.
One planet discovered outside the Kepler target area orbits a star easily visible with the naked eye. Right next to the 3.24 magnitude Sulafat, it is the 5.22 magnitude star HD 176051, with a planet 1.5 times the size of Jupiter in orbit around it.
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