Ozone vacuum-ultraviolet (VUV) ozone generators, employ a light source that generates a narrow-band ultraviolet light, a subset of that produced by the Sun. The Sun's UV sustains the ozone layer in the stratosphere of Earth. UV ozone generators use ambient air for ozone production, no air prep systems are used (air dryer or oxygen concentrator), therefore these generators tend to be less expensive. However UV ozone generators usually produce ozone with a concentration of about 0.5% or lower which limits the potential ozone production rate. Another disadvantage of this method is that it requires the ambient air (oxygen) to be exposed
S-1 (satellite) 4". "S-1" was the first geocentric orbit launch attempt for the rocket; its second attempt on August 14, 1959, carrying the "Beacon 2" inflatable sphere experiment to low Earth orbit, also failed. Eventually, both the Juno II and a re-launch of the "S-1" mission, designated "Explorer 7" or "S-1A", found success on October 13, 1959. The satellite, which ended its mission in August 1961, is still orbiting the Earth today. S-1 (satellite) S-1, also known as Explorer S-1 and Explorer 7X, was a geoscience satellite equipped with a suite of scientific instruments to study the environment around the Earth. The