Multiple star system in the constellation Hercules
Epsilon Herculis ,Latinized from ε Herculis, is a fourth-magnitude multiple star system in the northernconstellation ofHercules . The combinedapparent visual magnitude of 3.9111[ 1] parallax shift of 21.04 mas as seen from Earth,[ 1] light years from theSun . The system is moving closer to the Sun with aradial velocity of −25 km/s.[ 11]
There is disagreement over the properties of this system. Petrie (1939) classified two components asclass A0 and A2 with a visual magnitude difference of 1.5.[ 3] spectroscopic binary system with anorbital period of four days and aneccentricity of 0.02.[ 6] [ 3] stellar classification of A0 V,[ 2] [ 3] Lambda Boötis star ,[ 12] [ 13] [ 3]
InChinese ,天紀 Tiān Jì Celestial Discipline ξ Coronae Borealis ,ζ Herculis ,59 Herculis ,61 Herculis ,68 Herculis ,HD 160054 andθ Herculis .[ 14] Chinese name for ε Herculis itself is天紀三 Tiān Jì sān the Third Star of Celestial Discipline .)[ 15]
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