This neutral mass spectrometer is typical of those flown on Aerobee sounding rockets by the Aeronomy group at the Naval Research Laboratory (NRL). During the early 1950s the NRL carried out studies of the upper atmosphere by sending specialized instruments to extreme altitudes on Aerobee sounding rockets. Maximum altitude for these rockets was close to 230 kilometers. This radiofrequency mass spectrometer, which was designed by Willard H. Bennett when he was at the National Bureau of Standards, was used to determine the identity of the gases present in the near vacuum at extreme altitudes.
The compact size and light weight of this mass spectrometer makes it suitable for use in sounding rockets. This tube incorporates an element that ionizes uncharged (neutral) gases found in the upper atmosphere (see Catalogue #1987016000). It then determines the identity of those ions and consequently the atoms and molecules from which they arose. This instrument is similar to those that NRL sent aloft in the late 1950s in connection with the International Geophysical Year. This radio frequency mass spectrometer tube did not operate properly because the grids were spaced too closely.
The object was transferred to NASM by NRL in March 1986. It is currently stored at the Garber facility.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.