Normally, if you wanted to see a snake, you would look down, but that’s not the case with Serpens, an ancient star formation that slithered its way into Greek astronomer Ptolemy’s catalog of 48 constellations all the way back in the Second Century.
Serpens is a highly unusual constellation because it is split into two parts, separated by the constellation Ophiuchus, the Serpent Bearer. The two halves of the constellation are referred to a Serpens Caput, or the Serpent’s Head, and Serpens Cauda, or the Serpent’s Tail. Together, they contain 65 stars.
The constellation is bordered by Corona Borealis, BoÃ¶tes, Virgo, Libra, Ophiuchus, Hercules, Aquila, Sagittarius, and Scutum.
The brightest star in Serpens is Unukalhai, also known as Cor Serpentis, or “the Serpent’s Heart.” None of the other stars in this faint constellation are particularly bright.
Serpens is also home to a number of deep-sky objects, including the globular cluster M5, the stunning Eagle Nebula, and several galaxies — Hoag’s Object, ARP 220, and Seyfert’s Sextet, a close grouping of six galaxies.
Though there is much mythology surrounding snakes in numerous cultures and contexts, this specific serpent is connected to the story of Ophiuchus, which represents the Greek healer Asclepius. According to myth, Asclepius learned the secret of immortality from a serpent, but was killed by the god Zeus to prevent him from sharing this knowledge with the rest of humanity.