Xi Ursae Majoris (Alula Australis)

Xi Ursae Majoris (Alula Australis) is a double star in the constellation Ursa Major, magnitude 4.3.

The first binary star to have its orbit calculated (Félix Savary, 1827). Its components (magnitudes 4.3 and 4.8; spectral types F9 V (yellow-white) and G9 V (yellow)) lie 2.74″ apart at PA 131° (predicted for 2027.0 from its 59.9-year orbit).

When and where to see it

It is best placed in the evening sky around April, when it crosses the meridian at about 10 pm local time (around midnight in March). It can be seen from everywhere north of 58°S and never sets north of 58°N.

At its highest it stands 72° up from 50°N, 87° up from 35°N, 58° up from the equator, 23° up from 35°S.

Facts

Type

Double star

Constellation

Ursa Major

Designations

Alula Australis, ξ UMa, 53 UMa, 53 Ursae Majoris, STF 1523, HIP 55203

Magnitude

4.3

Position

RA 11h 18.2m, Dec +31° 32′ (J2000)

Open AstroPilot to see when Xi Ursae Majoris (Alula Australis) is highest tonight from your location, how easy it is with your telescope or binoculars, and an eyepiece view.