ETA SAGITTARII

'Eta Sagittarii' (η Sgr / η Sagitarii) is a star system in the constellation Sagittarius. The star system is 149 light years from Earth. It has the rarely used traditional names 'Sephdar' (Arabic الصفدر ''al-safdar''), meaning "Violent Warrior", and the Latin 'Ira Furoris', meaning "Fierce Wrath" or "Raging Anger" (of the Archer).
It was formerly known as "Beta Telescopii" (β Tel).
The primary component, η Sagittarii A, is a spectral type M3.5 red giant. It is a variable star with small magnitude fluctuations between +3.08 and 3.12, and is classified as an irregular variable.
The brightest companion, η Sagittarii B, is spectral class F dwarf star, with an apparent magnitude of +7.77. It is at a distance of 165 Astronomical Units from the primary and takes approximately 1 300 years to make one orbit. The two stars are separated by 3.6 arcseconds on the sky.
Farther out are two dimmer members of the system, the 13th magnitude η Sagittarii C, separated from A by 33 arcseconds, and the 10th magnitude η Sagittarii D, 93 arcseconds from A.

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★ HD 167618 -- Variable Star