Arcturus (α Boötis) is an orange giant, a massive star approximately 25 times the diameter of our younger Sun. Just under 37 light years from Earth, it is the brightest star in the northern part of the sky, and appears orange or yellow 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'.
- EarthSky: 'Star of the Week: Arcturus, orange star, cuts through galaxy’s disk'. 18th May 2011.