Lyra

Lyra ( /ˈlaɪərə/; Latin for lyre, from Greek λύρα)^[2] is a small constellation. It is one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations recognized by the International Astronomical Union. Its principal star, Vega — a corner of the Summer Triangle — is one of the brightest stars in the sky. Beginning at the north, Lyra is bordered by Draco, Hercules, Vulpecula, and Cygnus.^[3]

Lyra is visible from the northern hemisphere from spring through autumn, and nearly overhead, in temperate latitudes, during the summer months. From the southern hemisphere, it is visible low in the northern sky during the winter months.

Notable features

Stars

Lyra's brightest stars include the following:^[3]

• 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 in all; its spectral class is A0 V and it lies at a distance of only 25.3 ly.
• 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.
• δ¹ Lyr. A double star consisting of a blue-white star of mag. 6m and a semi-regular red giant.
• ε Lyr. A well-known quadruple star, also called "the Double Double" because each of the two brighter components is a double star.
• ζ Lyr. Another double star which can be split using binoculars.
• RR Lyr lends its name to a class of pulsating variable RR Lyrae-stars.

Deep-sky objects

In Lyra can be found the objects M56, M57, and Kuiper 90. M56 is a rather loose globular cluster at a distance of approximately 32,900 light-years, with a diameter of about 85 light years. Its apparent brightness is 8.3m. M57 is also known as the "Ring Nebula". It is one of the best known of all planetary nebulae; its integrated magnitude is 8.8m. It is thought to be between 6,000 and 8,000 years old as we see it today. Kuiper 90 is also known as 17 Lyrae C (Gliese 747AB), a red dwarf system near 17 Lyrae, but really at 26 light years from the Sun. Its period is 5 years, and its magnitude is 11.26 in the V band.^[3] BD +36 3317 [1], a white star in the young open cluster Stephenson 1, was discovered as a binary eclipsing system by Violat-Bordonau in 2008; its period is 4.30216 days; its other name is VSX J185422.2+365107 [2].

Exoplanets

Several exoplanets including WASP-3b, HAT-P-5b, GJ 758 b and c, HD 178911 Bb, HD 177830 b, TrES-1, and HD 173416 b have been discovered in Lyra. In January 2010 the Kepler Mission announced the discovery of the additional planets Kepler-7b, Kepler-8b, and at least two more planets in Kepler-9, which are expected to be the first of many discovered by the mission, which has a significant part of its field of view in Lyra.

History

In the past, Lyra was often represented on star maps as a vulture or an eagle carrying a lyre, either enclosed in its wings, or in its beak. It was sometimes referred to as Aquila Cadens or Vultur Cadens (falling eagle or falling vulture).^[4]

Mythology

In Greek mythology, Lyra was associated with the myth of Orpheus, the musician who was killed by the Bacchantes. After his death, his lyre was thrown into the river; Zeus sent an eagle to retrieve the lyre, and ordered both of them to be placed in the sky. In Wales, Lyra is known as King Arthur's Harp (Talyn Arthur), and King David's harp [3]. The Persian Hafiz called it the Lyre of Zurah.[4] It has been called the Manger of the Infant Saviour, Praesepe Salvatoris [5].

Equivalents in other astronomical systems

Vega and its surrounding stars are also treated as a constellation in other cultures.

In Australian Aboriginal astronomy, Lyra is known by the Boorong people in Victoria as the Malleefowl constellation.^[5]

Lyra was known as Urcuchillay by the Incas and was worshipped as an animal deity.^[6][7]

Fictional references

In the poem Aniara by the nobel laureate Harry Martinson, the space ship Aniara was travelling at high speed towards the stars of Lyra^[8] after having been shipwrecked by collisions by asteroids.

In the film K-PAX, the constellation of Lyra is the location of the planet K-PAX, which is an inhabited world that orbits twin stars and has seven moons.

In the film Contact, the message intercepted by Jodi Foster's character is coming from Vega, the brightest star in the Lyra constellation.

In the TV/Videogame series MegaMan Star Force, Lyra is the alien that accompanies Sonia Sky, who is otherwise known as Sonia Strumm in the game series, but Lyra is sometimes known as Harp, most commonly found in the original Japanese version, Ryuusei no Rockman.

Namesakes

USS Lyra (AK-101) was a United States Navy Crater class cargo ship named after the constellation.

Citations

Coordinates: 19^h 00^m 00^s, +40° 00′ 00″