The EXCEDE III rocket experiment successfully produced an artificial aurora on April 27, 1990, with an injected ~18-A beam of ~2.5-keV electrons. The experiment consisted of an accelerator module and a sensor module in a mother-daughter configuration. The beam was fired along the Earth's magnetic field lines between the altitudes of ~62 and 115 km during the flight. A major concern prior to the flight was that the injection of such an overdense electron beam into the lower ionosphere would charge the accelerator module to a significant fraction of the beam potential. To monitor the primary electrons remote from the rocket, two X ray proportional counters were included as part of the sensor module. X ray spectra from bremsstrahlung emission yield a direct measure of the primary electron beam energy outside the plasma sheath surrounding the accelerator module. Analysis of these spectra yields a beam energy of 2.2¿0.5 keV which indicates no substantial charging of the accelerator module for the entire time that the beam was on. We also find that the X ray intensity was modulated at the few percent level by firings of the attitude control jets. ¿ American Geophysical Union 1993