According to the object documentation, this detector was considered for use in the Goddard Space Flight Center solar spectrometer in the early 1960s (OSO 3 and OSO 5). This unit has a mica-end window and is a krypton-filled, halogen-quenched geiger tube. It is designed to operate in an external pressure range from 0 to 0.5 atmospheres.
The NASA Goddard Space Flight Center transferred this to the Museum in 1995.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.