what is it composed of ?
It consists mainly of molecular hydrogen and helium.
Uranus
The composition of Uranus's atmosphere is different from its bulk, consisting mainly of molecular hydrogen and helium. 
when was uranus first discovered and by who Sir William Herschel discovered it on 13 March 1781. is this a planet ? Yes, Uranus is the seventh planet from the Sun. how is the climate here ? It is the coldest planet in the Solar System. what is its reference in culture ? In astrology, it is the ruling planet of Aquarius. has is it been explored ? Yes, In 1986, NASA's "Voyager 2" interplanetary probe encountered it. how is the atmosphere there ? There is no well-defined solid surface within Uranus's interior, the outermost part of Uranus's gaseous envelope that is accessible to remote sensing. how did it get its name ? he name of Uranus references the ancient Greek deity of the sky Uranus. how is its visibility ? Its mean apparent magnitude is 5.68 with a standard deviation of 0.17, while the extremes are 5.38 and +6.03.
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Uranus [SEP] Composition
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 in the upper troposphere, which corresponds to a mass fraction . This value is close to the protosolar helium mass fraction of , indicating that helium has not settled in its centre as it has in the gas giants. The third-most-abundant component of Uranus's atmosphere is methane (). Methane has prominent absorption bands in the visible and near-infrared (IR), making Uranus aquamarine or cyan in colour. Methane molecules account for 2.3% of the atmosphere by molar fraction below the methane cloud deck at the pressure level of ; this represents about 20 to 30 times the carbon abundance found in the Sun.