Elnath

Elnath, also designated Beta Tauri, is a bright star in the northern celestial hemisphere that marks the tip of Taurus's northern horn. It is among the brightest stars in the constellation Taurus and lies near the Hyades cluster, with Zeta Tauri lying at the opposite horn.

Physically, Elnath is a blue-white B-type giant star, commonly classified as B7III, though some sources list a luminosity class of III–IV. It has an apparent visual magnitude of about 1.6 to 1.7 and sits at a distance of roughly 130 light-years (about 40 parsecs) from the Sun. The stellar surface temperature is around 12,000 kelvin, giving its characteristic blue-white hue. As a luminous star, its radius and luminosity exceed those of the Sun, though precise values depend on model assumptions.

Name and catalog tradition: The name Elnath (also El Nath) derives from Arabic astronomy and has appeared in both medieval Islamic and later Western star catalogs. The star bears the Bayer designation Beta Tauri.

Observational and cultural notes: Elnath is visible to the naked eye from most inhabited latitudes and is a prominent marker in the winter sky of the northern hemisphere. In terms of asterisms, it helps define Taurus’s horns together with Zeta Tauri, aiding stargazers in locating the surrounding features and the region of Taurus.