Arcturus is a STAR located in the constellation of Bootes, and is the brightest STAR in the night sky. It is also known as Alpha Bootis, and is a red giant STAR that is approximately 37 light years away from Earth. It is the fourth brightest STAR in the night sky, and is part of the Spring Triangle asterism. Arcturus is believed to be around 7 billion years old, and is one of the oldest stars visible to the naked eye.