Atmosphere of Triton by the ground-based observations, is slightly more abundant than methane. The abundance of methane relative to nitrogen increased by four to five times since 1986 due to the seasonal warming observed on Triton, which passed its solstice in 2001. Other possible components of the Triton's atmosphere include argon and neon. Because they were not detected in the ultraviolet part of the spectrum of Triton obtained by Voyager 2 in 1989, their abundances are unlikely to exceed a few percent. In addition to the gases mentioned above, the upper atmosphere contains significant amounts of both molecular and atomic hydrogen, which is
Noble gas compound where it is believed that the water molecule, a strong dipole, induces a weak dipole in the noble gas atoms, resulting in dipole-dipole interaction. Heavier atoms are more influenced than smaller ones, hence Xe•5.75 HO was reported to have been the most stable hydrate; it has a melting point of 24 °C. The deuterated version of this hydrate has also been produced. Noble gases can also form endohedral fullerene compounds where the noble gas atom is trapped inside a fullerene molecule. In 1993, it was discovered that when C is exposed to a pressure of around 3 bar of He