As befits a large constellation at the edge of the Milky Way, Ophiuchus is packed with deep-sky sights for observers with small and large telescopes. Open and globular star clusters abound here, along with many fine double stars. Let’s have a short tour of a handful of the highlights of the constellation, moving from easy objects to more difficult sights [Read more…] about Touring Clusters and Stars in OphiuchusShare This:
In last month’s constellation tour, you explored the faint stars of Serpens Caput, the Snake’s Head. This month, you examine the bearer of this celestial snake, a star group represented by the large constellation Ophiuchus.
Ophiuchus (pronounced “Oaf-ih-YOU-kus”) lies directly opposite the constellation Orion on the celestial sphere. But Ophiuchus is no Orion. The constellation has no bright stars, and you need to expend a fair effort to imagine here a man holding a snake. But Ophiuchus is chock-a-block with globular and open star clusters, as well as dark nebulae in its southern extremes near the border with the constellation Scorpius. In an upcoming article, you’ll get the highlights of the deep-sky sights in Ophiuchus. For now, let’s explore this ancient star group itself [Read more…] about The Constellation Ophiuchus, the Serpent BearerShare This:
One of the best targets for a quick stargazing session this time of year is the pretty but underappreciated open star cluster IC 4665. It’s a snap to find, beautiful to behold, and like most sky sights on Cosmic Pursuits, it’s visible from the northern and southern hemispheres.
IC 4665 is spread out over a full degree, more than twice the diameter of the full Moon, so it looks fainter than its integrated magnitude of 4.7. In dark sky, IC4665 is just barely visible to the unaided eye roughly 1° NE of the star Celebrai in the constellation Ophiuchus. Celebrai, or β (beta) Ophiuchi, is one of the stars in the distinctive asterism called Taurus Poniatowski, the “little bull”. If you’re battling light pollution, you’ll need binoculars to spot the cluster [Read more…] about IC 4665, the “HI” Star ClusterShare This: