Ophiuchus the Serpent Bearer is sometimes called the 13th constellation of the Zodiac. You can find many globular clusters here on summer evenings.
Ophiuchus the Serpent Bearer is a mythological snake handler. The snake that he holds is a separate constellation called Serpens. Serpens is broken in two and can be found on either side of Ophiuchus.
Locating the Constellation Ophiuchus
Ophiuchus is most easily found on summer evenings. It stays near the southern horizon, with the bottom portion of the constellation between Sagittarius's teapot asterism and the head of Scorpius the Scorpion. It is sometimes called the 13th constellation of the Zodiac because it lies on the ecliptic and, like the other 12 constellations of the Zodiac, planets occasionally lie among its stars. It is 11th largest of the 88 constellations.
Learning the Stars of Ophiuchus
There are five stars of 2nd magnitude in the Serpent Bearer. However, they are fairly spread out and don't suggest a distinctive or memorable shape. The most northerly of the 2nd magnitude stars is also the brightest, named Alpha Ophiuchi or Rasalhague, at magnitude 2.08. It lies relatively nearby at 47 light-years.
About eight degrees to the south of Alpha Ophiuchi is magnitude 2.76 Beta Ophiuchi, or Cebalrai. Beta Ophiuchi lies 82 light-years away. A nearly 24 degree jump south and west of Cebalrai is magnitude 2.73 Delta Ophiuchi, or Yed Prior. It lies 170 light-years away and is on the western border of the constellation. Nine degrees southeast of Delta Ophiuchi is magnitude 2.54 Zeta Ophiuchi, which lies 458 light-years away. The last 2nd magnitude star in Ophiuchus lies nine and a half degrees southeast of Zeta: Eta Ophiuchi. Eta Ophiuchi, or Sabik, is magnitude 2.43 and lies at a distance of 84 light-years.
Deep-Sky Targets in Ophiuchus
Seven Messier objects, all globular clusters, can be found in Ophiuchus. Starting at the last star we found, Eta Ophiuchi or Sabik, there are three globular clusters to the south. The first is a bit to the south-southeast and just three and a half degrees away. This globular cluster is M9 at magnitude 7.9. Eight and a half degrees to the south-southwest of M9 is globular cluster M19 at magnitude 7.2. And then almost four degrees straight south from M19 is the globular cluster M62 at magnitude 6.6. M62 lies on the border with Scorpius.
Back near Zeta Ophiuchi, a little less than three degrees south of the star, is globular cluster M107 at magnitude 8.1. The last three globulars are spread across the middle of the constellation. Eight degrees south of Beta Ophiuchi is M14 at magnitude 7.6. Ten degrees west of M14 is globular cluster M10 at magnitude 6.6. Lastly, just a little over three degrees to the northwest of M10 is M12, another magnitude 6.6 globular cluster.
