The Triangulum Galaxy is a spiral galaxy 2.73 million light-years from Earth in the constellation Triangulum. It is catalogued as Messier 33 or NGC 598. The Triangulum Galaxy is the third-largest member of the Local Group of galaxies, behind the Andromeda Galaxy and the Milky Way. It is one of the most distant permanent objects that can be viewed with the naked eye. Under exceptionally good viewing conditions with no light pollution, the Triangulum Galaxy can be seen with the 20/20 vision naked eye and to those viewers, it will sometimes be the farthest permanent entity visible without magnification. With a diameter of about 60,000 light-years, the Triangulum Galaxy is the third largest member of the Local Group of galaxies, roughly 60% the size of the Milky Way. It may be a gravitationally bound companion of the Andromeda Galaxy. Triangulum may be home to 40 billion stars, compared to 400 billion for the Milky Way, and 1 trillion stars for Andromeda Galaxy.