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
Gas-s-s-s and he only made one more movie before a twenty-year sabbatical. " A great deal of care went into what I was saying and how I was going to say it," he said of "Gas-s-s-s". "The finished picture does not evidently make all these points. It discourages me and so for a little while I prefer to step away ... Directing is very hard and very painful. Producing is easy. I can do it without really thinking about it." Corman did, however, go on to produce "Boxcar Bertha" for AIP. "Gas-s-s-s" found a fresh audience on late night television in