The lyre is one of the most ancient of musical instruments. For example,
in the royal city of Ur (circa 3000 BC) musicians played the lyre for
royalty, according to excavated artifacts.
In Greek mythology, the lyre was invented by Hermes. When only a child,
he pulled a cow-gut across a tortoise shell, and thereby created the
lyre. Hermes gave this lyre to his half-brother Apollo (both were fathered
by Zeus). As the god of music, Apollo became associated with the instrument.
Orpheus was given the instrument by Apollo when only a child, and the
Muses taught him to use it. Even Nature herself would stop to listen,
enraptured by his music.
When Eurydice, the wife of Orpheus, died from a snake bite and was taken
to the Underworld, Orpheus followed in hopes of bringing her back. His
playing convinced Hades to release Eurydice, providing Orpheus didn't look
back at her during the journey home - but just as he emerged into the
sunlight Orpheus turned and gazed upon his wife, and lost her forever.
There are several versions about the death of Orpheus. In the most
widespread version Dionysus invades Thrace, home of Orpheus, and the
female followers of Dionysus (the Maenads) tear Orpheus from limb to limb.
His head is thrown into the river Hebrus, where it floats to Lesbos, singing
the entire time.
The lyre of Orpheus is also thrown into the river, and it too floats to
Lesbos, beached near the temple of Apollo. Apollo then convinces Zeus
that the instrument should become a constellation. Zeus agrees, and
places the lyre of Orpheus between Hercules and Cygnus.
The constellation is small and rather faint, but it is home to the fifth
brightest star, Vega. The asterism resembles
some multi-legged creature more than it does a lyre, with Vega at the head.
The constellation hasn't the full complement of Bayer
stars, and only three stars are brighter than fourth-magnitude. Still,
there are some very fine objects to view.
Vega, "Falling Eagle" or "The Harp Star", is only the fifth
brightest star, but it dominates the summer skies in the northern
hemisphere, with a transit date of 1 July.
Beta Lyrae, sometimes known as "Sheliak" (Tortoise), is a
prototype of a variable star in which a close companion is transferring
matter to its gigantic primary. In Beta Lyrae's case, the transference
is occurring very rapidly. Eventually the system will become an Algol
variable. (See below for its values.)
About 12,000 years ago Vega served as the Pole Star, and it will again in
another 12,000 years.
Double stars in Lyra:
Delta2-Delta1 Lyrae form a wide binary that may
be gravitationally bound despite the great distance. The two have a nice
colour contrast, orange and blue. Note that delta2 is the
primary: 4.3, while delta1 has a visual magnitude of 5.6.
Beta Lyrae is a fixed multiple binary, with a primary of 3.5. AB:
3.5. 8.6; 149º, 46"; AE: 9.9, 318º, 67"; AF: 9.9, 19º, 85".
Epsilon1-Epsilon2 Lyrae: the famous "Double- Double".
All four stars are fifth-magnitude. The two principal stars form a very
wide binary: PA 173º, separation 208".
Each star is itself a double:
Epsilon1A-Epsilon1B is a slow binary with 1165 year orbit: 5.0, 6.1; PA 350º and separation 2.6".
is about twice as fast, with a period of 585 years: 5.2, 5.5; PA 83.5º, separation 2.3".
Zeta Lyrae is another relatively fixed multiple. The brightest
component is D: AD 4.3, 5.9; 150º, 43.7". The other components
are fourteen magnitude.
Struve 2470 and Struve 2474 form another fine double-double,
that some say is equal to epsilon1,2.
Struve 2470: 6.6, 8.6; 271 degrees, 13.4" and Struve 2474:
6.5, 8.6; 261º, 16.4".
The two binaries are found two and a half degrees NE of gamma Lyrae, which is the brightest star in the region. Or, if you can find iota Lyrae, drop south one and a half degrees. It's a sight well worth the detour!
Variable stars in Lyra:
Alpha Lyrae (Vega) is a delta Scuti type variable, fluctuating
from -0.02 to 0.07 every four hours 33.6 minutes.
Beta Lyrae is an EB variable: 3.25 to 4.4 with a period of
RR Lyrae is a prototype for a pulsating type of variable with
short periods, usually less than twenty-four hours. RR Lyrae's period
is 13h36m, and it changes in magnitude from 7.1 to 8.1.
Deep Sky Objects in Lyra:
There are two Messier objects in Lyra: M56 and M57.
M56 (NGC 6729) is a globular cluster, very condensed. It is found
eight degrees due south of theta Lyrae.
M57 (NGC 6720) known as the Ring Nebula, is the finest
planetary nebula in the skies. The ring itself should be clearly visible
in medium scopes, while the fourteen magnitude central star may take
a little longer. Burnham gives an excellent discussion on this object.
It is located between beta and gamma Lyrae (slightly closer to beta),
and is about 4000 light years distant.