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|List of stars in Ophiuchus|
|Symbolism:||the snake-holder / the healer|
|Right ascension:||17 h|
|Area:||948 sq. deg. (11th)|
|Brightest star:||α Oph (Ras Alhague) (2.1m)|
|Nearest star:||Barnard's Star (5.96 ly)|
Northern May Ophiuchids
Southern May Ophiuchids
|Visible at latitudes between +80° and −80°|
Best visible at 21:00 (9 p.m.) during the month of July
Ophiuchus (Ὀφιοῦχος IPA: /ˌɒfiːˈjuːkəs/) is a large constellation located around thecelestial equator. Its name is Greek for 'snake-holder', and it is commonly represented as a man grasping the snake that is represented by the constellationSerpens. Ophiuchus was one of the 48 constellations listed by the 1st centuryastronomer Ptolemy, and it remains one of the 88 modern constellations. It was formerly referred to as Serpentarius (/ˌsɚpənˈtɛəriəs/), a Latin word meaning the same is its current name.
Ophiuchus is a zodiacal constellation (meaning that the Sun passes through it during the course of the year), but unlike the other twelve, it is not counted as anastrological sign by astrologers. As of 2008, the sun passes through Ophiuchus between November 30th and December 17th.
It is located between Aquila, Serpens and Hercules, northwest of the center of theMilky Way. The southern part lies between Scorpius to the west and Sagittariusto the east. It is best visible in the northern summer and located opposite Orion in the sky. Ophiuchus is depicted as a man grasping a serpent; the interposition of his body divides the snake constellation Serpens into two parts, Serpens Caput and Serpens Cauda, which are nonetheless counted as one constellation.
RS Ophiuchi is part of a class called recurrent novae, whose brightness increase at irregular intervals by hundreds of times in a period of just a few days. It is thought to be at the brink of becoming a type-1a supernova.
Barnard's Star, one of the nearest stars to the Solar System (the only stars closer are the Alpha Centauri binary star system and Proxima Centauri), lies in Ophiuchus. (It is located to the left of β and just north of the V-shaped group of stars in an area that was once occupied by the now-obsolete constellation ofTaurus Poniatovii, Poniatowski's Bull.)
In April 2007, astronomers announced that the Swedish-built Odin satellite had made the first detection of clouds of molecular oxygen in space, following observations in the constellation Ophiuchus.
The supernova of 1604 was first observed on October 9, 1604, near θ Ophiuchi.Johannes Kepler saw it first on October 16 and studied it so extensively that thesupernova was subsequently called Kepler's Supernova. He published his findings in a book titled De stella nova in pede Serpentarii (On the New Star in Ophiuchus's Foot). Galileo used its brief appearance to counter the Aristotelian dogma that the heavens are changeless.
Ophiuchus contains several star clusters, such as IC 4665, NGC 6633, M9, M10, M12, M14, M19,M62, and M107, as well as the nebula IC 4603-4604. The unusual galaxy merger remnant NGC 6240 is also in Ophiuchus.
|This section may contain original research or unverified claims. Please improve the article by adding references. See the talk page for details. (December 2008)|
There exist a number of theories as to whom the figure represents.
The most recent interpretation is that the figure represents the healer Asclepius, who learned the secrets of keeping death at bay after observing one serpent bringing another healing herbs. To prevent the entire human race from becoming immortal under Asclepius' care, Zeus killed him with a bolt of lightning, but later placed his image in the heavens to honor his good works. It has also been noted that the constellation Ophiuchus is in close proximity in the sky to that of Sagittarius, which has at times been believed to represent Chiron (the mentor of Asclepius and many other Greek demigods), though Chiron was originally associated with the constellation Centaurus.
Another possibility is that the figure represents the Trojan priest Laocoön, who was killed by a pair of sea serpents sent by the gods after he warned the Trojans not to accept the Trojan Horse. This event was also memorialized by the sculptors Agesander, Athenodoros, andPolydorus in the famous marble sculpture Laocoön and his Sons, which stands in the Vatican Museums.
Although Ophiuchus intersects the ecliptic, it is not a zodiacal sign in most versions of astrology. The signs are defined as more-or-less 30-degree segments of the ecliptic, of which there are twelve, and they are named after nearby constellations at the time the system was developed, rather than being defined by the modern constellations. However, a few sidereal astrologers consider the sun to be in the sign Ophiuchus when it is in the constellation Ophiuchus, which as of 2008 is November 30 to December 17.
- Ian Ridpath and Wil Tirion (2007). Stars and Planets Guide, Collins, London. ISBN 978-0007251209. Princeton University Press, Princeton. ISBN 978-0691135564.
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