Atmosphere of Earth the border between the atmosphere and outer space. Atmospheric effects become noticeable during atmospheric reentry of spacecraft at an altitude of around . Several layers can be distinguished in the atmosphere, based on characteristics such as temperature and composition. The study of Earth's atmosphere and its processes is called atmospheric science (aerology). Early pioneers in the field include Léon Teisserenc de Bort and Richard Assmann. The three major constituents of Earth's atmosphere are nitrogen, oxygen, and argon. Water vapor accounts for roughly 0.25% of the atmosphere by mass. The concentration of water vapor (a greenhouse gas) varies significantly from around
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