A groung Fabry-Perot interferometer has been used to measure atomic oxygen nightglow (OI 630.0nm) from the thermosphere (about 250km) at King Sejong station (KSS, geographic: $62.22^{circ}$S, $301.25^{circ}$E; geomagnetic: $50.65^{circ}$S, $7.51^{circ}$E), Antarctica. While numerous studies of the thermosphere have been performed on high latitude using ground-based Fabry-Perot interferometers, the thermospheric measurements in the Southern Hemisphere are relatively new and sparse. Therefore, the nightglow measurements at KSS play an important role in extending the thermospheric studies to the Southern Hemisphere. In this study, we investigated the effects of the geomagnetic and solar activities on the thermospheric neutral temperatures that have been observed at KSS in 1989 and 1997. The measured average temperatures are 1400K in 1989 and 800K in 1997, reflecting the influence of the solar activity. The measurements were compared with empirical models, MSIS-86 and semi-empirical model, VSH.