Alpha Trianguli

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**α Trianguli**
Observation data Epoch J2000.0
Constellation (pronunciation)	Triangulum
Right ascension	01^h 53^m 04.9^s
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
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 also has the traditional names Metallah or Ras al Muthallah, and Caput Trianguli which derive from phrases meaning "the head of the triangle".

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.

Metallah 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.