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Spectral TypeK1.5 III
Temperature4,286 K
K1.5 III TypeConstellation: Boötes

Arcturus

Alpha Boötis

Arcturus is a red giant and one of the brightest stars in the northern sky.

Distance
36.7 ly
Light Years from Earth
Age
7.1 billion years
Estimated
Mass
1.08 M☉
Relative to Sun
Radius
25.4 R☉
Relative to Sun
Surface Temp
4,286 K
Effective Temp
Luminosity
170 L☉
Total Energy Output

Astrophysical Data

Apparent Magnitude-0.05
Absolute Magnitude-0.31
Spectral ClassificationK1.5 III

Size Comparison

Sun (1 R☉)
Arcturus (25.4 R☉)