Equatorial atmosphere measurements obtained with the sounding rocket grenade experiment

Under a grenade series of experiments with sounding rockets made at Barreira do Inferno, Natal (5.6°S, 35°W), 19 successful launchings have yielded useful data on the upper stratosphere and the mesosphere during the period August 7, 1966, to March 5, 1968. These experiments covered the height range of about 35–95 km and were supplemented by radiosonde data from 19 balloons that provided data up to approximately 35 km. Also, data from 29 meteorological rockets with an upper limit of 60 km are available for the period September 14, 1966, to July 24, 1968. Only 2 of these 29 launchings were instrumented for temperature measurements. Data on winds, temperatures, and densities have been obtained and analyzed from the rocket-grenade and balloon experiments. Some features of the wind and temperature distributions in the upper stratosphere and mesosphere are discussed. Extremely low mesopause temperatures of the order of 130°K were noticed in early summer at about 90 km. The temperature at this height was found to be higher in winter than in summer. A correlation between temperature at 40 km and absorption of cosmic noise at 30 MHz is also presented as a probable evidence of stratosphere-ionosphere coupling.