Astronotes Armagh Planetarium's Stellar Blog! ... Moon . ... Now these moons are actually quite small with UranusтАЩs largest moon Titania having half the diameter of our own moon! ... The rest of the moons of Uranus are a lot smaller with many astronomers believing that they are actually captured asteroids and in comparison to some of the other systems of satellites orbiting around the other planets even UranusтАЩs major moons arenтАЩt exactly big but they still have their peculiarities. ...