Serpens

Serpens is a constellation of the northern hemisphere. One of the 48 constellations listed by the 2nd century astronomer Ptolemy, it remains one of the 88 modern constellations defined by the International Astronomical Union. It is unique among the modern constellations in being split into two non-contiguous parts, Serpens Caput (Serpent's Head) to the west and Serpens Cauda (Serpent's Tail) to the east. Between these two halves lies the constellation of Ophiuchus, the "Serpent-Bearer". In figurative representations, the body of the serpent is represented as passing behind Ophiuchus between μ Ser in Serpens Caput and ν Ser in Serpens Cauda. The brightest star in Serpens is Unukalhai or Cor Serpentis "Serpent's Heart", with an apparent magnitude of 2.63. Part of the Milky Way passes through Serpens Cauda, which is therefore rich in deep-sky objects, such as the Eagle Nebula (IC 4703) and its associated star cluster Messier 16. The nebula measures 70 light-years by 50 light-years and contains the Pillars of Creation, three dust clouds that became famous for the image taken by the Hubble Space Telescope. Located in Serpens Caput are Seyfert's Sextet, one of the densest galaxy clusters known, and Arp 220, the prototypical ultraluminous infrared galaxy. In addition, it also contains the Hercules–Corona Borealis Great Wall, the largest object in the universe.

References

Found in HGS Manual on Page 108

Found in HGS Manual on Page 115