The constellation of Lyra is one of the easier figures to spot in late Sum-mer/ early fall. It is anchored by one of the brightest stars in the sky, Vega. In fact, Vega is the fifth brightest star in the night sky blaring at a magnitude 0.3. You can easily spot Vega overhead in the summer after twilight. Vega was known in earlier civilizations as a swooping Vulture. In Babylonian astronomy, is identified with Dilgan, the Messenger of Light, a name also applied to other stars. At one time, 12,000 to 15,000 BCE, Vega/Wega was the Pole-star, the star marking the North Pole, called in Ak-kadian Tir-anna ("Life of Heaven"), and in Assyrian Daya-same ("Judge of Heaven"). Due to the precession of the equinoxes, Polaris is now our Pole Star; "the still point in the turning world". The Chinese called Vega She-niu, the weaver, and her beloved shepherd, Altair, who meet once a year, crossing the Milky Way. Christians saw Lyra as King David's harp.1 Vega is one of the corners of the Summer Triangle along with Deneb of Cygnus the Swan and Altair of Aquilla the Eagle.
Of course the Lyre comes from ancient mythology. Lyra the harp is said to be the magic harp that was given to Orpheus by Mercury or Apollo. The music of Orpheus charmed every person or animal, and most of all, the beautiful nymph Eurydice, whom Orpheus married. When she died, Orpheus was so grief stricken that even Pluto took pity on him. Pluto offered Orpheus the chance to carry Eurydice out of Hades and have her once again. The only condition was that Orpheus must not gaze at his beloved until he was out of the underworld. This he could not do, and once he turned his eyes upon her, she vanished and he never saw her again. After Orpheus died, Jupiter placed his harp in the sky.
The shape of Lyra can be seen in decent skies and are easily exposed in dark skies, even near twilight. The following stars make most of the shape of the lyre; Sheliak or Beta Lyrae (ß) shines at magnitude 3.5, Sulufat or Gamma Lyrae (shines at a optically identical magnitude 3.3; Delta Lyrae (shines at magnitude 5.5.
Lyra lies on the edge of the Milky Way and has a very nice backdrop of stars to enrich telescopic objects. Of course, Lyra contains perhaps the most famous of all of Charles Messier’s catalog, M57 which is better known as the Ring Nebula. This wonderful object now a White Dwarf star that has thrown off it’s outer shell in an expanding ring. M57 is known as a planetary nebula, although technically, planets have nothing to do with it. Planetary nebulae are formed in the dying stages of a star when the core fusion reactions decline to the extent that the star's structure cannot be supported - gravity forces the outer part of the star to collapse inwards, causing the inner part to condense and heat up. The intense build up of pressure and radiation causes the outer shell to 'explode' and be driven away. The intense stellar wind causes the surrounding gases to ionize in bright colors. The core remnant at the centre of M57 was once a star of even greater mass than the Sun. Having ejected its outer layers into space, it is destined to die as a tiny white dwarf star, about the size of the Earth.2
An often overlooked Messier object is M56 which is a nice sight but is forgotten due to the popularity of M57. It is one of the less bright Messier globulars, especially lacking the bright core which most globulars have. Nevertheless it is not too difficult to resolve, even at its rather large distance of 31.6 kly. M56 was one of Messier's original discoveries; he saw it first on January 23, 1779. It shines at a magnitude of 8.3 and is 7 arc minutes wide.
M56 courtesy of SEDS
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M56 courtesy of SEDS
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M56 & M57 are among the easier star hops. M57 has to be in the top 10% of easiest to find objects. It lies on a direct line between Gamma Lyrae and Beta Lyrae! See the image to the left as well as Fig. 1. M56 also lies on a direct line but between Gamma Lyrae and Alberio in Cygnus. M56 is roughly six degrees from that fa-mous double star, Alberio. Starting at Alberio, slew the scope directly towards the tip of the Lyre, gamma Lyrae.
Here are detailed pictures of Lyra's double stars
Lyra is extremely rich in double stars, some of which are the most popular. In fact the most well known double of all is a ‘double-double.’
Epsilon Lryae is easily split into two components, but needs a steady night to further split these two magnitude 6.0 components into four.
Beta Lyrae, is a half separated eclipsing binary of a cream-white color. The brightness varies from 3.4 mag to 4.3 mag every twelve days and 22 hours.
Delta Lyrae star is wide and easy to split, and shows a pretty red-orange and blue-white pair. It is a good object for all telescopes. With a huge separation of 10 arc minutes or about 1/3 the size of the moon at the same magnification. This pair, shining at a magnitude 5.5, can be seen easily with a 60mm scope and larger scopes at very low power.
Zeta Lyrae is easy to find and relatively easy to split. Magnitude difference is obvious. Separation is just 44 arc minutes. The brighter component seems perhaps slightly bluish.
Two other nice doubles are Struve 2470 and 2474.
- Andy Weeks