Measurement of mesospheric ozone by the S-310-6 rocket experiment

The preliminary results obtained from the S-310-6 rocket experiment by using the solar ultraviolet absorption method are given about the altitude distribution of mesospheric ozone. The experiment was carried out at Uchinoura (31 deg 15 min N, 131 deg 05 min E) on January 19, 1979, at 1750 JST (solar zenith angle = 93 deg) under evening twilight condition. In this experiment, four photometers were used, each photometer consisting of an interference filter and a phototube. The photometers were mounted in the nose cone of the rocket in sets of two photometers, each set 180 deg apart in the plane normal to the rocket spin axis. A mono-axial sun-following system was designed and used for the experiment. This sun follower cancels the precessional motion of the rocket. The altitude profiles of ozone concentration measured by the S-310-6 experiment represented typical winter time, mid-latitude profiles, and are expected to be more accurate than the earlier winter measurements in which a sun follower system was not used. The comparison with the ozone concentration values obtained earlier confirmed that the ozone concentration in winter time was larger than that in summer time in the upper stratosphere and the mesosphere as reported earlier. (J.P.N.)