Theta Tauri

Theta Tauri (θ Tau, θ Tauri) is a double star in the constellation Taurus and a member of the Hyades open cluster. It dominated by two 3rd magnitude stars, θ¹ Tauri and θ² Tauri, which are separated by 5.62 arcminutes (0.094°) on the sky. Based upon parallax measurements, the first component, θ¹ Tauri, is located at a distance of 154.4 ly (47.3 pc), while the second component, θ² Tauri is at a distance of 150.4 light-years (46.1 parsecs). If these estimates are correct, then the two components are separated by about four light years and hence are unlikely to form a binary star system.

θ¹ Tauri is the dimmer star, an orange K-type giant with an apparent magnitude of +3.84. θ² Tauri is a white A-type giant with a mean apparent magnitude of +3.40. θ² Tauri is classified as a Delta Scuti type variable star and its brightness varies from magnitude +3.35 to +3.42 with a period of 1.82 hours.

Both bright stars are spectroscopic binaries and have at least one closer companion. θ¹ Tauri has a 7th magnitude companion 0.082 arcseconds, or at least 4 astronomical units (AU), away from the primary. θ² has a 6th magnitude companion 0.005 arcseconds, or at least 2 AU, distant. It completes an orbit once every 141 days.

The Yucatec Maya say that this star is chakumuy, the name of small bird.