Upsilon Tauri (υ Tauri) is a solitary, white-hued

star A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

in the

zodiac The zodiac is a belt-shaped region of the sky that extends approximately 8° north and south celestial latitude of the ecliptic – the apparent path of the Sun across the celestial sphere over the course of the year. Within this zodiac ...

constellation of

Taurus Taurus is Latin for 'bull' and may refer to: * Taurus (astrology), the astrological sign ** Vṛṣabha, in vedic astrology * Taurus (constellation), one of the constellations of the zodiac * Taurus (mythology), one of two Greek mythological ch ...

, and is a member of the

Hyades Hyades may refer to: *Hyades (band) *Hyades (mythology) *Hyades (star cluster), an open star cluster in the constellation Taurus {{Disambiguation it:Iadi ...

star cluster A star cluster is a group of stars held together by self-gravitation. Two main types of star clusters can be distinguished: globular clusters, tight groups of ten thousand to millions of old stars which are gravitationally bound; and open cluster ...

. It is faintly visible to the naked eye with an

apparent visual magnitude Apparent magnitude () is a measure of the brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction of the object's light ca ...

of +4.3. Based upon an annual parallax shift of 21.21

mas Mas, Más or MAS may refer to: Film and TV * Más y Menos, fictional superhero characters, from the Teen Titans animated television series * "Más" (''Breaking Bad''), a season three episode of ''Breaking Bad'' Music Albums * ''Más'' (album), ...

seen from Earth, it is around 154

light year A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distance, astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by t ...

s from the Sun.

Properties

This is an

A-type main sequence star An A-type main-sequence star (A) or A dwarf star is a main-sequence (hydrogen burning) star of spectral type A and luminosity class (five). These stars have spectra defined by strong hydrogen Balmer absorption lines. They measure between 1.7 ...

with a

stellar classification In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction gratin ...

of A8 Vn. It is classified as a Delta Scuti type

variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are ...

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 An equatorial bulge is a difference between the equatorial and polar diameters of a planet, due to the centrifugal force exerted by the rotation about the body's axis. A rotating body tends to form an oblate spheroid rather than a sphere. On ...

that is 9% larger than the polar radius. Occasionally this star system shares the

Bayer designation A Bayer designation is a stellar designation in which a specific star is identified by a Greek alphabet, Greek or Latin letter followed by the genitive case, genitive form of its parent constellation's Latin name. The original list of Bayer design ...

''υ Tauri'' with

72 Tauri 72 Tauri (abbreviated 72 Tau) is a possible binary star in the zodiac constellation of Taurus. It is faintly visible to the naked eye with an apparent visual magnitude of +5.5, although only 0.29° from the brighter υ Tauri. Based upon ...

, which is separated from it by 0.29° in the sky.

Naming

With φ, κ¹, κ² and χ, 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 : φ as ''Alkalbain I'', χ as ''Alkalbain II'', κ¹ as ''Alkalbain III'', κ² as ''Alkalbain IV'' and this star (υ) as ''Alkalbain V''.

References

{{DEFAULTSORT:Upsilon Tauri Delta Scuti variables A-type main-sequence stars Hyades (star cluster) Tauri, Upsilon Taurus (constellation) Durchmusterung objects Tauri, 069 020711 028024

1392 Year 1392 ( MCCCXCII) was a leap year starting on Monday (link will display full calendar) of the Julian calendar. Events January–December * June 13 – An assassination attempt by Pierre de Craon against Olivier de Clisson, C ...