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Venus.

Earth.

Mars.

Titan.

Jupiter.

Saturn.

World	Surface pressure in millibars	Composition by number of molecules
Jupiter	High	86% H2, 13% He, 0.07% CH4
Saturn	High	97% H2, 3% He, 0.05% CH4
Neptune	High	> 74% H2, < 25% He, > 1% CH4 at depth
Uranus	High	83% H2, 15% He, 2% CH4 at depth
Earth	1000	78% N2, 21% O2, 0.8% Ar, 0.8% Ne, 0.03% CO2
Venus	90,000	96% CO2, 3.4% N2, 0.14% H2O
Mars	10	95% CO2, 3% N2, 1.6% Ar, 0.13% O2, 0.03% H2O
Titan	1500	> 90% N2, 1%-10% CH4, ? Ar