Arcturus

Arcturus is the brightest star in the northern celestial hemisphere and the fourth-brightest in the night sky. It is an aging red giant in Bootes that has exhausted the hydrogen in its core and moves at high velocity relative to the Sun.

Stellar Data

Notable Facts

• Arcturus is the brightest star in the northern celestial hemisphere
• Its light was used to open the 1933 Chicago World's Fair via a photoelectric cell
• It moves through space at about 122 km/s relative to the Sun