Electrostatic analyzer measurements of ions of the SCATHA satellite show evidence of locally generated ions. These measurements come during periods of large negative charging (~-100 to -10,000 V) at or near geosynchronous altitude. Ions are observed at energies below the satellite potential, which, in the absence of scattering, must have been generated on or near the satellite surface. Differential charging measurements from the surface satellite potential monitor indicated that there were surfaces with the proper magnitude of differential charging to provide a source for the observed ions. Application of the Sigmund-Thompson theories on sputtering show that ambient 10 to 100-keV O+ on glass could provide a yield of 0.5--1.0 particles per incident ion. Roughly 2--4% of this yield is ionized. This is sufficient to explain the flux levels observed. Particle tracking using the NASA charging analyzer program (NASCAP) showed that the energies measured provided a sweep of trajectories along the satellite surface, but no specific source was identified. ¿American Geophysical Union 1991