2.7.2 https://spdx.org/licenses/ SPDX CC0-1.0 https://spdx.org/licenses/CC0-1.0.html Creative Commons Zero v1.0 Universal CC0 1.0 Universal is the Creative Commons license applicable to all publicly available SPASE metadata descriptions spase://SMWG/NumericalData/ICON/EUV-FUV/L3/Oplus/PT12S NASA NumericalData ICON Extreme Ultraviolet and Far Ultraviolet Oplus data EUV and FUV Oplus data 2026-08-18T00:00:00Z 2026-08-18T00:00:00Z First release. JMW. This describes the Level 3.2 data product for ICON which is in NetCDF4 format. These files are named ICON_L3-2_YYYY-MM-DD_vXXrZZZ.NC, where YYYY-MM-DD is the year month day, XX shows the version number and ZZZ shows the revision number of this file. Each individual file contains one calendar day (24 hours) of data, merging data from the EUV and FUV Level 2 ionosphere products. The 12-second integration time is preserved in all samples. For FUV, the central 4 of 6 imaging stripes are used to match the EUV 12-deg horizontal field of regard. All data are filtered to remove flagged bad data (FUV Level 2.5 Data Quality = 0 in any of the 4 stripes, and EUV Level 2.6 Data Warning = 2). Consult the Level 2 data files for more information. Altitude profiles are generated on a 5-km resolution altitude grid. FUV data in all 4 stripes are binned and averaged using a weighted mean. EUV altitude profiles are interpolated onto the grid. Each data source has been evaluated for precision to meet the original ICON science goals and requirements, but may require systematic offsets or scaling for accuracy in alternate applications, for details see: Nighttime (FUV) O+ validation : https://doi.org/10.1007/s11214-023-00970-2 Daytime (EUV) O+ validation : https://doi.org/10.1007/s11214-022-00930-2" National Aeronautics and Space Administration; Dr. Andrew Stephan; Dr. Farzad Kamalabadi; Dr. Thomas J. Immel Stephan, A.; and F. Kamalabadi 2026-06-16T00:00:00 Space Physics Data Facility National Aeronautics and Space Administration Explorers Program NNG12FA44C National Aeronautics and Space Administration Explorers Program contracts NNG12FA42I spase://SMWG/Person/Andrew.W.Stephan PrincipalInvestigator spase://SMWG/Person/Farzad.Kamalabadi PrincipalInvestigator spase://SMWG/Person/James.M.Weygand MetadataContact Additional information on ICON https://icon.ssl.berkeley.edu/ ICON spacecraft Homepage. Design and Performance of the ICON EUV Spectrograph https://doi.org/10.1007/s11214-017-0384-2 Space Science Reviews, 212(1-2), pp.631-643. DOI: 10.1007/s11214-017-0384-2 The far ultra-violet Imager on the ICON mission https://doi.org/10.1007/s11214-017-0386-0 Space Science Reviews, 212(1-2), pp.655-696. DOI: 10.1007/s11214-017-0386-0 spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb Online Open https://spdx.org/licenses/ SPDX CC0-1.0 https://spdx.org/licenses/CC0-1.0.html Creative Commons Zero v1.0 Universal CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products CDAWeb HAPI Server https://cdaweb.gsfc.nasa.gov/hapi ICON_L3-2_O-Plus Web Service to this product using the HAPI interface. NetCDF National Aeronautics and Space Administration; Dr. Andrew Stephan; Dr. Farzad Kamalabadi; Dr. Thomas Immel. spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb Online Open https://spdx.org/licenses/ SPDX CC0-1.0 https://spdx.org/licenses/CC0-1.0.html Creative Commons Zero v1.0 Universal CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products HTTPS from SPDF https://spdf.gsfc.nasa.gov/pub/data/icon/l3/o-plus ICON_L3-2_O-Plus Access to Data in NetCDF Format via https from SPDF CDAWeb https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?dataset=ICON_L3-2_O-Plus&index=sp_phys ICON_L3-2_O-Plus Access to ASCII, NetCDF, CDF, and Plots via NASA/GSFC CDAWeb NetCDF None National Aeronautics and Space Administration; Dr. Andrew Stephan; Dr. Farzad Kamalabadi; Dr. Thomas Immel. Calibrated ICON EUV and FUV team spase://SMWG/Instrument/ICON/EUV spase://SMWG/Instrument/ICON/FUV ImageIntensity 2019-11-16T00:00:00Z 2022-11-25T23:59:59Z PT12S Earth.NearSurface.Atmosphere Earth.NearSurface.Ionosphere Epoch Time Epoch Time corresponding to the center of each observation, in milliseconds since Jan 1 1970. PT12S ms 0 6000000000000 -999 Magnitude Temporal UTC Time String ICON_L32_UTC_Time "UTC time corresponding to the measurement. PT12S " " Magnitude Temporal Geodetic Latitude ICON_L32_Latitude Geodetic Latitude. PT12S degrees -90 90 -999 Direction Positional Geodetic Longitude ICON_L32_Longitude Geodetic longitude at retrieval location, in WGS referenced to 300 km tangent point for daytime (EUV), and to HmF2 tangent point location for nighttime (FUV). PT12S degrees 0 360 -999 Direction Positional O+ Density Altitude ICON_L32_Altitude Altitude corresponding to the retrieved quantities, in WGS84 in 5 km increments, centered, e.g. 150 km means 147.5 km <= Altitude < 152.5 km. PT12S km -999 Direction Positional Magnetic Latitude ICON_L32_Magnetic_Latitude Quasi-dipole magnetic latitude at retrieval location, referenced to 300 km tangent point for daytime (EUV), and to HmF2 tangent point location for nighttime (FUV) calculated using the fast implementation developed by Emmert et al. (2010, doi:10.1029/2010JA015326) and the Python wrapper apexpy (https://github.com/aburrell/apexpy/). PT12S degrees -90 90 -999 Direction Positional Magnetic Longitude ICON_L32_Magnetic_Longitude Quasi-dipole magnetic longitude at retrieval location, referenced to 300 km tangent point for daytime (EUV), and to HmF2 tangent point location for nighttime (FUV) calculated using the fast implementation developed by Emmert et al. (2010, doi:10.1029/2010JA015326) and the Python wrapper apexpy (https://github.com/aburrell/apexpy/). PT12S degrees -180 180 -999 Direction Positional HMF2 ICON_L32_HmF2 Height of the peak electron density of the F2 layer from retrieval, in WGS. PT12S km 0 1000 -999 Scalar Positional HmF2 Error ICON_L32_HmF2_Error 1-sigma uncertainty in height of the F2 layer peak from retrieval, as determined from the reported statistical uncertainties and/or weighted averaging of the measurements. PT12S km 0 1000 -999 StandardDeviation Other NMF2 ICON_L32_NmF2 Electron density at the peak of the F2 layer from retrieval. PT12S 1/cm^3 0 10000000000 -999 Electron Moment NumberDensity NmF2 Error ICON_L32_NmF2_Error 1-sigma uncertainty in electron density at the peak of the F2 layer as determined from the reported statistical uncertainties and/or weighted averaging of the measurements. PT12S 1/cm^3 0 10000000000 -999 Electron StandardDeviation NumberDensity O+ Profile ICON_L32_Oplus Number density of O+ as a function of altitude. PT12S 1/cm^3 -999 Ion Average NumberDensity 8 O+ Profile Error ICON_L32_Oplus_Error 1-sigma uncertainty in the number density of O+ as a function of altitude as determined from the reported statistical uncertainties and/or weighted averaging of the measurements. PT12S 1/cm^3 -999 Ion StandardDeviation NumberDensity 8 Local Solar Time ICON_L32_Local_Solar_Time Local Solar Time at retrieval location. PT12S hours 0 24 -999 Direction Positional Solar Zenith Angle ICON_L32_Solar_Zenith_Angle Solar Zenith Angle at retrieval location. PT12S degrees 0 180 -999 Direction Positional Data Source ICON_L32_Data_Source Data product contributing to each O+ measurement. Value: 2.5 is FUV nighttime ionosphere, 2.6 is EUV daytime ionosphere. PT12S hours 2 2.9 -999 InstrumentMode