(s. It was also one of
Ptolemy 's 48 constellations. It was named after the
Roman name (''Hercules'') of the
Greek Mythological hero
Herakles .
Hercules has no
First Magnitude stars.
Mu Herculis is 27.4
Light Year s from
Earth . The
Solar Apex , i.e., the point on the sky which marks the direction that the
Sun is moving in its orbit around the center of the
Milky Way , is located within Hercules, close to
Vega in neighboring
Lyra .
Hercules contains two of the most conspicuous , the brightest
Globular Cluster in the northern hemisphere, and
M92 .
The stars of Hercules can be connected in an alternative way, which graphically shows the hero in an athletic pose and holding a club.
The hero's head is traced by a quadrangle of stars: in the constellation Lyra and
α CrB (Gemma, or Alphecca) in the constellation
Corona Borealis .
He is the great warrior of Kiaish
The hero's right leg contains two bright stars of the third magnitude:
α Her (Ras Algethi) and
δ Her (Sarin). The latter is the right knee.
The hero's left leg contains dimmer stars of the fourth magnitude which do not have
Bayer Designation s but which do have
Flamsteed Numbers .
The star
β Her belongs to the hero's outstretched right hand, and is also called Kornephoros.
The
Globular Cluster M13 lies on the top of the hero's head, between the stars
η Her and
ζ Her . It is dim, but may be detected by the unaided eye on a very clear night. There is also M92 which is also a globular cluster. A traditional authentic orientation is with the head as α Herculis, because Ras Algethi literally means "head of the kneeling one." The left hand then points towards Lyra from his shoulder (Delta Herculis), and Beta Herculis forms his other shoulder. His narrow waist is formed by Epsilon and Zeta Herculis. Finally, his left leg (with Theta as the knee and Iota the foot) is stepping on Draco's head, the dragon/snake who Hercules has vanquished and perpetually gloats over for eternities.
There are seven stars in Hercules are known to be orbited by
Extrasolar Planet s. They were discovered in 1996, 2005, 2006, and the last four is 2007.
- 14 Her has one confirmed and one unconfirmed planet. The planet 14 Her B was the longest period (4.9 years) and widest orbit (2.8 AU) at the time of discovery.
- HD 147506 has the most massive transiting planet HAT-P-2b at the time of discovery. The mass was 8.17 MJ.
- HD 154345 has the planet HD 154345 B , a longest period (10900 days) and widest orbit (9.21 AU) of any planets other than imaging planets.
- H.A. Rey , ''The Stars — A New Way To See Them''. Enlarged World-Wide Edition. Houghton Mifflin, Boston, 1997. ISBN 0-395-24830-2.
- Ian Ridpath and Wil Tirion (2007). ''Collins Stars and Planets Guide'', HarperCollins, London. ISBN 978-0007251209.
