Top Qs
Timeline
Chat
Perspective

Alpha Columbae

Star in the constellation Columba From Wikipedia, the free encyclopedia

Alpha Columbae
Remove ads

Alpha Columbae or α Columbae, officially named Phact (/ˈfækt/),[12][13] is a third magnitude star in the southern constellation of Columba. It has an apparent visual magnitude of 2.6,[2] making it the brightest member of Columba. Based upon parallax measurements made during the Hipparcos mission, Alpha Columbae is located at a distance of around 261 light-years (80 parsecs).[1]

Quick Facts Constellation, Right ascension ...
Remove ads

Nomenclature

α Columbae, Latinized to Alpha Columbae, is the star's Bayer designation.

The traditional name of Phact (also rendered Phad, Phaet, Phakt)[14] derives from the Arabic فاختة fākhitah 'ring dove'. It was originally applied to the constellation Cygnus and later transferred to this star.[15][16][17][18] The etymology of its name hadāri (unknown meaning)[19] has also been suggested. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[20] to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016[21] included a table of the first two batches of names approved by the WGSN; which included Phact for this star.

In Chinese, 丈人 (Zhàng Rén), meaning Grandfather, refers to an asterism consisting of α Columbae and ε Columbae.[22] Consequently, α Columbae itself is known as 丈人一 (Zhàng Rén yī, English: the First Star of Grandfather.).[23] From this Chinese name, the name Chang Jin has appeared[24]

Remove ads

Properties

This is believed to be a solitary star,[10][25] although it has a faint optical companion at an angular separation of 13.5 arcseconds, making it a double star.[26] The stellar classification of Alpha Columbae is B9Ve,[3] matching a B-type main-sequence star. The spectrum shows it to be a Be star surrounded by a hot gaseous disk, which is generating emission lines because of hydrogen recombination.[14] Like most if not all such stars, it is rotating rapidly with a projected rotational velocity of 176 km s−1. The azimuthal equatorial velocity may be 457 km s−1.[10] It is a suspected Gamma Cassiopeiae type (GCAS) variable star, with its apparent magnitude varying from 2.62m to 2.66m.

Remove ads

References

Loading related searches...

Wikiwand - on

Seamless Wikipedia browsing. On steroids.

Remove ads