2.7.1 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://NASA/NumericalData/Alouette2/SFS/PT32S NASA NumericalData Alouette 2 Topside Electron Density Profiles Manually Scaled at CRC 2025-12-04T13:28:27Z 2021-04-27T15:38:11Z Only known prior ReleaseDate of the metadata 2025-12-04T13:28:27Z Added MetadataRightsList and RightsList(s). Added ResourceType and NamingAuthority. Updated to 2.7.1. Changed http to https in top-level schemaLocation attribute. Fixed version number separator in top-level schemaLocation attribute. ZCB This data set, provided by the Communications Research Centre (CRC) in Ottawa, Canada, consists of electron density profiles derived from Alouette 2 Sweep-Frequency Sounder for the ionosphere above the F2 maximum (topside ionosphere). The data set was originally provided on an EBCDIC magnetic tape written on an IBM 360 computer. The electron density profiles were computed from digital values of frequency and virtual height, scaled from ionograms. The data are ordered chronologically and include about 11,000 profiles. Telemetry stations are not identified, but satellite location, Greenwich mean time of observation, solar zenith angle at the satellite, dip latitude at the satellite, total electron content down to the lowest height of topside signal reflection (normally near 300 km), and other relevant information is noted with each profile. The format gives sequences of numbers for each point scaled from the ionogram. These sequences include electron density at the successive points, and the coefficients a2, b3, b4, b5, etc. from which geometric heights can be calculated, using formulas 40 and 41 in J. E. Jackson, "The reduction of topside ionograms to electron-density profiles," Proceedings of the IEEE., p. 960, June 1969. These formulas can also be used to calculate interpolated density-height values. A CRC interpolation program available at NSSDC can be used with this data set. The ionograms were selected for their scientific interest and comprise only a very small portion of reductions possible from the available ionograms. Data obtained prior to March 9, 1970, are also available on microfiche from NSSDC. spase://SMWG/Person/Dieter.K.Bilitza GeneralContact spase://VSPO/NumericalData/P_ALOUETTE2_HDR_NEPROF spase://VSPO/NumericalData/Alouette2/SFS/PT32S 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 FTPS from SPDF (not with most browsers) ftps://spdf.gsfc.nasa.gov/pub/data/alouette/topside_sounder/crc_ne_profile_cdf/alouette2/ HTTPS from SPDF https://spdf.gsfc.nasa.gov/pub/data/alouette/topside_sounder/crc_ne_profile_cdf/alouette2/ In CDF via HTTP from CDAWeb CDAWeb https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?dataset=ALOUETTE2_NEPROF_TOPS&index=sp_phys ALOUETTE2_NEPROF_TOPS ALOUETTE2_NEPROF_TOPS CDF spase://SMWG/Repository/NASA/GSFC/SPDF 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 ALOUETTE2_NEPROF_TOPS Web Service to this product using the HAPI interface. CSV CALIBRATED spase://SMWG/Instrument/Alouette2/SFS ThermalPlasma 1965-12-15T09:40:15 1972-07-10T22:37:22 PT32S Earth.NearSurface.Ionosphere