Atmosphere of Triton asymmetry was actually observed during star occultations by Triton in 1990s. Before Voyager 2 arrived, a nitrogen and methane atmosphere with a density as much as 30% that of Earth had been suggested. This proved to be a great overestimate, similar to the predictions of the atmospheric density of Mars, but like on Mars, a denser early atmosphere is postulated. Voyager 2 flew past Triton five hours after closest approach to Neptune in mid-late August 1989. During the flyby, Voyager 2 took measurements of the atmosphere, finding methane and nitrogen in the atmosphere. In the 1990s, observations from Earth were
Atmosphere of Jupiter streamers—are still used. Other terms such as vorticity, vertical motion, cloud heights have entered in use later, in the 20th century. The first observations of the Jovian atmosphere at higher resolution than possible with Earth-based telescopes were taken by the "Pioneer" "10" and "11" spacecraft. The first truly detailed images of Jupiter's atmosphere were provided by the "Voyagers". The two spacecraft were able to image details at a resolution as low as 5 km in size in various spectra, and also able to create "approach movies" of the atmosphere in motion. The Galileo Probe, which suffered an antenna problem, saw