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Ophiuchus, 13th constellation of Zodiac


Tonight for July 16, 2015

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The faint constellation Ophiuchus the Serpent Bearer appears in the southern sky at mid-to-late evening at this time of year. It descends into the southwest sky as evening deepens into late night. Ophiuchus is sometimes called the 13th or forgotten constellation of the Zodiac. The sun passes in front of Ophiuchus from about November 29 to December 17. And yet no one ever says they’re born when the sun is in Ophiuchus. That’s because Ophiuchus is a constellation – not a sign – of the Zodiac.

The 12 signs of the Zodiac represent equal 30o divisions of sky, whereas the 13 constellations of the Zodiac are of various sizes. Although the sun resides in front of each zodiacal sign for about a month, the sun is in front of the constellation Virgo for about one and one-half months and the constellation Scorpius for about a week.

Look for Ophiuchus above the bright ruddy star Antares, the brightest in the constellation Scorpius the Scorpion. (Incidentally, in 2015, you’ll also see the golden planet Saturn in the vicinity of Antares.) Ophiuchus’ brightest star – called Rasalhague – highlights the head of Ophiuchus and is nowhere as bright as Antares or Saturn. Ophiuchus will continue to be visible in the south to southwest sky (above Antares) on August and September evenings.

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Sky chart of the constellation Ophiuchus

On sky maps, Ophiuchus the Serpent Bearer is depicted as holding Serpens the Serpent, which is considered a separate constellation. According to ancient Greek star lore, Ophiuchus is Asclepius, the physician who concocted a healing potion from the Serpent’s venom, mixing it with the Gorgon’s blood and an unknown herb. This potion gave humans access to immortality, until the god of the underworld appealed to Zeus to reconsider the ramifications of the death of death.

Even today, the Staff of Asclepius – the symbol of the World Heath Organization – pays tribute to the constellation Ophiuchus the Serpent Bearer. Will you see faint Ophichus, the overlooked zodiacal constellation, tonight?

Read more: Born between November 29 and December 18? Here’s your constellation

Dates of sun’s entry into each constellation of the Zodiac

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