Topix Underground

"..English astronomer William Lassell was born #OTD in 1799.

He built his own 24" diameter telescope, and devised steam-driven equipment for grinding an polishing the speculum metal mirror. This telescope was the first of its size to be mounted “equitorially” to allow easy tracking of the stars. He independently co-discovered Hyperion, a moon of Saturn. He also discovered Triton, a moon of Neptune, and Ariel and Umbriel, satellites of Uranus. .."