Gamma Herculis  Gamma Herculis, Latinized from γ Herculis, is a magnitude 3.74 binary star system in the northern constellation of Hercules. This is known to be a spectroscopic binary system, although there is no information about the secondary component. Based upon parallax measurements, this system is located at a distance of about from the Earth. The spectrum of the primary star matches a stellar classification of A9III, which indicates this is a giant star that has exhausted the hydrogen at its core and evolved away from the main sequence. The effective temperature is about 7,031 K, giving the star a white hue characteristic of A-type stars. It is rotating rapidly with a projected rotational velocity of . The interferometry-measured angular diameter of this star is , which, at its estimated distance, equates to a physical radius of about six times the radius of the Sun.  Observations by German astronomer Ernst Zinner in 1929 gave indications that this may be a variable star. It was listed in the "New Catalogue of Suspected Variable Stars" (1981) with a magnitude range of 3.74 to 3.81. Further observations up to 1991 showed a pattern of small, slow variations with a magnitude variation of 0.05. These appeared to repeat semi-regularly with a period of 183.6 days, although the spectroscopic data presented a longer period of 165.9 days. It was a member of indigenous Arabic asterism "al-Nasaq al-Sha'āmī", "the Northern Line" of "al-Nasaqān" "the Two Lines", along with β Her (Kornephoros), γ Ser (Zheng, Ching) and β Ser (Chow). According to the catalogue of stars in the "Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars", "al-Nasaq al-Sha'āmī" or "Nasak Shamiya" were the title for three stars :β Ser as "Nasak Shamiya I", γ Ser as "Nasak Shamiya II", γ Her as "Nasak Shamiya III" (exclude β Her)  In Chinese, (), meaning "Right Wall of Heavenly Market Enclosure", refers to an asterism which is represent eleven old states in China which is marking the right borderline of the enclosure, consisting of γ Herculis, β Herculis, κ Herculis, γ Serpentis, β Serpentis, δ Serpentis, α Serpentis, ε Serpentis, δ Ophiuchi, ε Ophiuchi and ζ Ophiuchi.