An informative, up-to-date, beautifully illustrated introduction to Uranus, Neptune and their moons. The most distant planets in our solar system, Uranus and Neptune were unknown by the ancients – Uranus was discovered in the 1780s and Neptune only in the 1840s. Our first sighting and subsequent investigation of both planets have been hampered by their sheer distance from Earth: there has only been one close encounter, Voyager 2 in the late 1980s. The Voyager mission revealed many enticing details about the planets and their moons, but also left many more questions unanswered.