Atmosphere of Jupiter hydrogen sulfide (HS), ammonia (NH) and phosphine (PH). Their abundances in the deep (below 10 bar) troposphere imply that the atmosphere of Jupiter is enriched in the elements carbon, nitrogen, sulfur and possibly oxygen by factor of 2–4 relative to the Sun. The noble gases argon, krypton and xenon also appear in abundance relative to solar levels (see table), while neon is scarcer. Other chemical compounds such as arsine (AsH) and germane (GeH) are present only in trace amounts. The upper atmosphere of Jupiter contains small amounts of simple hydrocarbons such as ethane, acetylene, and diacetylene, which form from methane
Atmosphere of Uranus from the analysis of "Voyager 2" far infrared and radio occultation observations. The currently accepted value is in the upper troposphere, which corresponds to a mass fraction . This value is very close to the protosolar helium mass fraction of , indicating that helium has not settled towards the centre of the planet as it has in the gas giants. The third most abundant constituent of the Uranian atmosphere is methane , the presence of which has been known for some time as a result of the ground-based spectroscopic observations. Methane possesses prominent absorption bands in the visible and near-infrared,