A moon for Mars! Asaph Hall finds Phobos 149 years ago

On this date in 1877, astronomer Asaph Hall discovered a moon for Mars: Phobos, the larger of 2 moons. He discovered the other moon, Deimos, later that year. The post A moon for Mars! Asaph Hall finds Phobos 149 years ago first appeared on EarthSky .