Rasalhague

At a distance of only about 49 light-years, Rasalhague is one of the nearest stars in this group and the brightest of Ophiuchus, where it carries the Alpha designation. It is a white A-type star with a colour index of 0.155, slightly warmer in tint than the reddened giants but cooler than the pure blue-white stars. Rasalhague appears at apparent magnitude 2.08, and its absolute magnitude of 1.22 — the faintest intrinsic value among these bright stars — shows that much of its prominence in the sky derives from its closeness rather than from exceptional luminosity. It crowns the large constellation of the Serpent-Bearer, high in the summer sky of the northern hemisphere.