Hercules (hûrˈkyəlēzˌ) [key], in astronomy, northern constellation located between Lyra and Corona Borealis. It is traditionally depicted as the hero Hercules in a kneeling position. There are no very bright stars in Hercules and only three of third magnitude, the brightest of which, Ras Algethi (Alpha Herculis), is a red giant and possibly the largest visible star in the sky. The constellation contains the globular star cluster M13, barely visible to the naked eye but spectacular even in a small telescope. Hercules reaches its highest point in the evening sky in late July.