Uranus (mythology) three one-hundred-handed giants the Hekatonkheires, and the one-eyed giants the Cyclopes. Uranus imprisoned Gaia's youngest children in Tartarus, deep within Earth, where they caused pain to Gaia. She shaped a great flint-bladed sickle and asked her sons to castrate Uranus. Only Cronus, youngest and most ambitious of the Titans, was willing: he ambushed his father and castrated him, casting the severed testicles into the sea. For this fearful deed, Uranus called his sons Titanes Theoi, or "Straining Gods." From the blood that spilled from Uranus onto the Earth came forth the Giants, the Erinyes (the avenging Furies), the Meliae (the
Moons of Uranus had been seen. In the 1840s, better instruments and a more favorable position of Uranus in the sky led to sporadic indications of satellites additional to Titania and Oberon. Eventually, the next two moons, Ariel and Umbriel, were discovered by William Lassell in 1851. The Roman numbering scheme of Uranus's moons was in a state of flux for a considerable time, and publications hesitated between Herschel's designations (where Titania and Oberon are Uranus II and IV) and William Lassell's (where they are sometimes I and II). With the confirmation of Ariel and Umbriel, Lassell numbered the moons I through IV