Characterization of the atmosphere has a paramount importance to study, understand and predict climatological phenomena. In particular, and in the scope of satellite navigation, accurate measurement of tropospheric delays experienced by GNSS ranging signals, due to refraction, is a very powerful tool to monitor the neutral atmosphere and, more specifically, characterize the integrated water vapor (IWV). On the basis of the tropospheric delays, either computed through precise-point positioning solutions (e.g. GMV’s magicPPP) or available models, the IWV can be computed by separating this delay in terms of the zenith hydrostatic (ZHD) and wet (ZWD) components. Complementary, study of the ionosphere and its characterization is also very interesting to understand solar cycles and analyze space weather (i.e. solar radiation, ionospheric storms). Being able of measuring and predicting space weather, and its impact in the ionosphere layer, is of great importance for many kinds of applications, such as high frequency communications, remote sensing radars or Safety-of-Life GNSS applications (e.g. SBAS). Characterization of ionosphere can be performed in different ways, as the measurement of the Total Electron Content (TEC) in the line of sight Slant TEC (STEC), or in the vertical component (VTEC), or the variation of this TEC through time. By relying on GNSS pseudorange and carrier-phase measurements, magnitude of TEC can be measured either by precise methods, such as those presented in  and , or through widely used ionospheric models. The Unexplored Antarctica Expedition 2018-2019 hosted the ESA’s GESTA (Galileo Experimentation & Scientific Tests in Antarctica) experiment. The experiment collected more than one week of GNSS raw data from a Septentrio PolaRx 5 receiver along 2000 km inside the Antarctica plateau and acquired the southernmost measurement of Galileo signals at almost 80 deg South Latitude. This data will be used as input to analyze the GNSS signals navigation performance at high latitude, and for the study of tropospheric and ionospheric delays, studying different metrics of interest (e.g. ZHD, ZWD, TEC, RoT). The resulting conclusions will allow to provide guidelines and inputs to feed other scientific experiments and models using GNSS data.