Upsilon Tauri (ÃÂ Tauri) is a solitary, white-hued star in the zodiac constellation of Taurus, and is a member of the Hyades star cluster. It is faintly visible to the naked eye with an apparent visual magnitude of +4.3. Based upon an annual parallax shift of 21.21 mas seen from Earth, it is around 154 light years from the Sun.
This is an A-type main sequence star with a stellar classification of A8 Vn. It is classified as a Delta Scuti type variable star and its brightness varies from magnitude +4.28 to +4.31 with a period of 3.56 hours. At an estimated age of 827 million years, it is spinning rapidly with a rotation period of just 0.415 days. This is giving the star an oblate shape with an equatorial bulge that is 9% larger than the polar radius.
Occasionally this star system shares the Bayer designation àTauri with 72 Tauri, which is separated from it by 0.29ð in the sky.
With ÃÂ, ú<sup>1</sup>, ú<sup>2</sup> and ÃÂ, it composed the Arabic were the Arabs' Al Kalbain, the Two Dogs. According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, Al Kalbain were the title for five stars : àas Alkalbain I, àas Alkalbain II, ú<sup>1</sup> as Alkalbain III, ú<sup>2</sup> as Alkalbain IV and this star (à) as Alkalbain V.