Alpha Trianguli

α Trianguli

Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Triangulum
Right ascension	01h 53m 04.9s
Declination	+29° 34' 44"
Apparent magnitude (V)	+3.41
Distance	64.1 ± 1.0 ly (19.7 ± 0.3 pc)
Spectral type	F6IV
Other designations
Mothallah, Metallah, Ras al Muthallah, Elmuthalleth, Caput Trianguli, 2 Trianguli, HR 544, HD 11443, BD+28 312, FK5 64, HIP 8796, SAO 74996, GC 2272, CCDM 01531+2935

Alpha Trianguli (α Tri, α Trianguli) is a binary star in the constellation Triangulum. It has the traditional names Mothallah or Ras al Muthallah (alternate spellings Mathallah, Metallah, Ras al Mothallah, Elmuthalleth), and Caput Trianguli, from the Arabic رأس المثلث ra’s al-muθallaθ "the head of the triangle" and its Latin translation.

Alpha Trianguli is a yellow-white F-type subgiant with a mean apparent magnitude of +3.41. Its mass is about 1.5 times that of the Sun and its diameter is about 3 times as large as the Sun's.

Mothallah is a spectroscopic binary whose components have an orbital period of only 1.74 days. The companion star is a mere 6 million km (3.7 million miles) from the main star. The whole system is approximately 64.1 light years from Earth.

α Tri is listed as UR.BAR.RA "The Wolf", bearing the epithet "the seeder of the plough" in the MUL.APIN, listed after "The Plough", the name for a constellation formed of Triangulum plus Gamma Andromedae^[1].

References

1. ^ Rogers, J. H. (February 1998). "Origins of the ancient constellations: I. The Mesopotamian traditions". Journal of the British Astronomical Association, no.1 108: 9–28. Bibcode 1998JBAA..108....9R. 

External links

• Alpha Tri