Atmosphere of Earth and balloons, and too low to permit orbital spacecraft. The mesosphere is mainly accessed by sounding rockets and rocket-powered aircraft. The stratosphere is the second-lowest layer of Earth's atmosphere. It lies above the troposphere and is separated from it by the tropopause. This layer extends from the top of the troposphere at roughly above Earth's surface to the stratopause at an altitude of about . The atmospheric pressure at the top of the stratosphere is roughly 1/1000 the pressure at sea level. It contains the ozone layer, which is the part of Earth's atmosphere that contains relatively high concentrations of
Views of Lyndon LaRouche and the LaRouche movement Science & Technology", which conducted what has been called "a very effective campaign of misinformation on the issue of ozone depletion", published "The Holes in the Ozone Scare" in 1992. The book, by LaRouche followers Rogelio Maduro and Ralf Schauerhammer, said that chlorofluorocarbons (CFCs) were not destroying the ozone layer and opposed the proposal to ban them. It asserted that most chlorine in the atmosphere came from oceans, volcanoes, or other natural sources, and that CFCs were too heavy to reach the ozone layer. It went on to say that even if the ozone layer were depleted there would not