Antares is a red supergiant STAR located in the constellation of Scorpio. It is one of the brightest STARS in the night sky and is often referred to as the 'heart of the Scorpion'. Antares is also known as Alpha Scorpii, and is the 15th brightest STAR in the sky. It is estimated to be about 600 light years away from Earth. The term Antares is derived from the Greek words meaning 'anti-Ares' or 'rival of Mars', referring to its reddish hue which is similar to that of the planet Mars.