Arcturus (star)

Arcturus (α Boötis) is a red giant, a star reaching the end of its life. Just under 37 light years from Earth and approximately 25 times the diameter of our younger Sun, it is the brightest star in the northern part of the sky, and appears orange in colour. It is moving rapidly relative to the Solar System, as part of the Arcturus stream with 52 other stars, and in about 4,000 years will reach its closest point to the Sun. Arcturus can be identified via another 'arc', namely the shape of the Big Dipper's handle; following this line of stars leads to Arcturus, in the constellation of Boötes, 'the Herdsman'.