Uranus is the farthest planet we can barely see with the naked eye. The green-blue gas ball needs 84 years to go around the sun once. Already with simple telescopes the moons Titania and Oberon can be observed.
On the poster, the five great moons Miranda, Ariel, Umbriel, Titania and Oberon are presented in fascinating photographs of the Voyager probe from 1986, which has so far been the only probe to visit the gas planet.
Uranus still has at least 16 other moons, which were discovered only after 1985 and circle in some over 20 million kilometers away around the planet.