Ozone has no affect on the determination of the stellar visual magnitude system we use. The NASA 'TOMS' satellite provides daily measurements of the amount of ozone in the atmosphere, especially above the arctic and antarctic regions as the above image indicates. Globally, the ozone layer averages approximately 300 Dobson Units, which would correspond to a layer about 1/8th of an inch (3 millimeters) thick at the Earth's surface, about the thickness of two stacked pennies. In contrast, during the annual Antarctic ozone "hole," the amount of ozone in the ozone "hole" is about 100 Dobson Units, about 1/25th of an inch, or approximately the thickness of a single dime. The above image was obtained from data on October 3, 1999 during the 'ozone hole' season over the antarctic. From the Press Release "NASA satellites show the size of the region of depleted Antarctic ozone (shown in blue) extended to a record 10.5 million square miles on Sept 19,1998. In this image obtained on October 3, 1999 the size of the Antarctic ozone hole is smaller than it was at the same time last year. Red colors denote high ozone levels; blue denotes low."
Copyright 1997 Dr. Sten Odenwald
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