The Far-UltraViolet (FUV) imager onboard the Ionospheric Connection Explorer (ICON) spacecraft provides two-dimensional limb images of oxygen airglow in the nightside low-latitude ionosphere that are used to determine the oxygen ion density. As yet, no FUV limb imager has been used for climatological analyses of Equatorial Plasma Bubbles (EPBs). To examine the potential of ICON/FUV for this purpose, we statistically investigate small-scale (~180 km) fluctuations of oxygen ion density in its limb images. The seasonal-longitudinal variations of the fluctuation level reasonably conform to the EPB statistics in existing literature. To further validate the ICON/FUV data quality, we also inspect climatology of the ambient (unfiltered) nightside oxygen ion density. The ambient density exhibits (1) the well-known zonal wavenumber-4 signatures in the Equatorial Ionization Anomaly (EIA) and (2) off-equatorial enhancement above the Caribbean, both of which agree with previous studies. Merits of ICON/FUV observations over other conventional data sets are discussed in this paper. Furthermore, we suggest possible directions of future work, e.g., synergy between ICON/FUV and the Global-scale Observations of the Limb and Disk (GOLD) mission.

1. INTRODUCTION
2. SPACECRAFT, INSTRUMENT, AND DATAPROCESSING
3. RESULTS
    3.1 An Example of Equatorial Plasma Bubbles (EPBs) in theIonospheric Connection Explorer/Far-UltraViolet (ICON/FUV) Images
    3.2 Statistics of Ionospheric Connection Explorer/Far-UltraViolet (ICON/FUV) Ambient [O+]
    3.3 Statistics of Ionospheric Connection Explorer/Far-UltraViolet (ICON/FUV) Equatorial Plasma Bubbles (EPBs)
4. DISCUSSIONS AND CONCLUSIONS
ACKNOWLEDGMENTS
ORCIDs
REFERENCES

• Jaeheung Park(Space Science Division, Korea Astronomy and Space Science Institute,Department of Astronomy and Space Science, Korea University of Science and Technology) Corresponding author
• Stephen B. Mende(Space Sciences Laboratory at University of California at Berkeley, CA 94720, USA)
• Richard W. Eastes(Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, Boulder, CO 80303, USA)
• Harald U. Frey(Space Sciences Laboratory at University of California at Berkeley, CA 94720, USA)