Sections

Catalogues

Show the direction and distance to this object on the Galactic Map.

Proper Names	Mothallah, Caput Trianguli, Metallah, Ras al Mothallah
Bayer Designation	Alpha Trianguli
Flamsteed Number	2 Trianguli
HR (BSC)	544
HD	11443
Constellation	Triangulum
Right Ascension	1h 53m 5s
Declination	+29° 34' 44"
Distance	63 light years 19 parsecs
Magnitude	Apparent: +3.4 Absolute: +2.0
Spectral Class	F5III bright yellow giant
Optimum Visibility	October / November
Notes	Mothallah is an ellipsoidal star, in which its rapid rate of rotation have caused it to flatten at the poles and expand at the equator. As the star shifts its orientation relative to Earth, it presents different aspects of this ellipsoidal form, causing its magnitude to vary over time. It possesses a small binary companion in a close and rapid orbit.

This orange subgiant, about 63 light years from Earth, takes its name from the Arabic al muthallath, meaning 'the Triangle' and, despite its 'Alpha' designation, is the second brightest star in the northern constellation of that name.

Imagery provided by Aladin sky atlas

v2.1g