Uranus appears as a greenish disk from the earth. Uranus was not discovered until 1781. Over 60 years later, when scientists noted that something beyond Uranus was affecting its motion, Neptune was discovered.
            Period of revolution: 84.01 years. Period of rotation: 23 hours (reverse motion). Main components of atmosphere: Hydrogen, helium, methane. Known moons: 15 (though a couple of websites I found state 21) Temperatures: Day -151°C; Night (?).