Uranus
The composition of Uranus's atmosphere is different from its bulk, consisting mainly of molecular hydrogen and helium. The helium molar fraction, i.e. the number of helium atoms per molecule of gas, is 0.15±0.03 in the upper troposphere.
Source: Wikipedia
rotation time
17.2 Hours
revolution time
84 Years
radius
25,362 KM
average temp.
-195°c