Daytime measurement of positive and negative ion composition to 131 km by rocket-borne spectrometer

The ambient positive and negative ion composition in the mass range 5 to 60 atomic mass units was measured between 93 and 131 km by two Bennett radiofrequency mass spectrometers.1 The spectrometers were flown in Aerobee rocket NRL No. 24 at White Sands Proving Ground, New Mexico, at 10:16 MST, November 29, 1955. Except for the time of day and year, this experiment was identical to the night-time experiment previously reported.2 Again, the experimental equipment performed well, the mass spectra were apparently not influenced by the rocket or its gases, and interpretation of the telemetered data was simple and unambiguous.