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/Collection/ISIS1/SFS/Ionogram/PT29S NASA Collection ISIS 1 Topside Sounder Ionograms ISIS-1 Topside Sounder Ionogram CDFs at NASA's CDAWeb https://doi.org/10.48322/7njf-d645 2025-12-04T13:29:41Z 2026-05-15T13:29:41Z ISIS 1 Collection metadata of ionograms created. JMW These ionograms were digitized from the original ISIS-1 7-track analog telemetry tapes using the facilities of the former Data Evaluation Laboratory at the NASA/GSFC. This data restoration project is headed by Dr. R.F. Benson (NASA/GSFC). Ionograms were digitized at the rate of 40,000 16-bit samples/sec. This sample rate is higher than the Nyquist frequency of 30 kHz. The sample frequency of 40 kHz provides a measurement every 25 microseconds corresponding to an apparent range (c*t/2) interval of 3.75 km. Each ionogram consists of a fixed-frequency and and a swept-frequency portion. The time resolution between ionograms is typically 29 seconds. Users please acknowledge the Coordinated Data Analysis Web (CDAWeb) at the NASA Goddard Space Flight Center, ISIS-1 SFS instrument Principal Investigator J. H. Whitteker and ISIS Data-Restoration project lead Robert F. Benson. Whitteker, James H. 2025-11-14T16:02:28Z Space Physics Data Facility spase://SMWG/Person/James.H.Whitteker PrincipalInvestigator spase://SMWG/Person/Robert.F.Benson GeneralContact spase://SMWG/Person/Dieter.K.Bilitza GeneralContact ISIS/Alouette Topside Sounder Data Restoration Project https://nssdc.gsfc.nasa.gov/space/isis/isis-status.html ISIS/Alouette page maintained by NASA GSFC with science and instrument descriptions, data access, software, and publication lists en NSSDC's Master Catalog https://nssdc.gsfc.nasa.gov/nmc/experiment/display.action?id=1969-009A-01 Information about the Sweep Frequency Sounder experiment on ISIS-1. spase://VWO/NumericalData/ISIS1/SFS/ISIS1_Ionogram_CDF_PT29S spase://VWO/NumericalData/ISIS1/SFS/Ionogram.PT29S spase://VSPO/NumericalData/ISIS1/SFS/Ionogram/PT29S 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 HTTPS from SPDF https://spdf.gsfc.nasa.gov/pub/data/isis/topside_sounder/ionogram_cdf/isis1/ HTTPS access to repository of ISIS-1 Ionograms in CDF format at NASA CDAWeb en CDAWeb https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?dataset=I1_AV_ALL&index=sp_phys I1_AV_ALL Repository of ISIS-1 data in CDF format at NASA CDAWeb, accessible via web interface. en CDF None Users please acknowledge the Coordinated Data Analysis Web (CDAWeb) at the NASA Goddard Space Flight Center, ISIS-1 SFS instrument Principal Investigator J. H. Whitteker and ISIS Data-Restoration project lead Robert F. Benson. 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 I1_AV_ALL@0 I1_AV_ALL@1 Web Service to this product using the HAPI interface. CSV Users please acknowledge the Coordinated Data Analysis Web (CDAWeb) at the NASA Goddard Space Flight Center, ISIS-1 SFS instrument Principal Investigator J. H. Whitteker and ISIS Data-Restoration project lead Robert F. Benson. ISIS-1 Topside Sounder Average Ionogram over Fairbanks, AK: ULA, Latitude 65, Longitude 212 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Fairbanks/PT29S 1975-01-04T18:15:16Z 1979-09-14T12:06:35Z Spherical GEO 65 212 ISIS-1 Topside Sounder Average Ionogram over Kashima, Japan: KSH, Latitude 36, Longitude 141 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Kashima/PT29S 1978-01-06T04:52:17Z 1981-12-30T16:22:49Z Spherical GEO 36 141 ISIS-1 Topside Sounder Average Ionogram over Kerguelen Island, France: KER, Latitude -49, Longitude 70 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/KerguelenIsland/PT29S 1983-08-24T15:21:21Z 1983-12-30T15:19:33Z Spherical GEO -49 70 ISIS-1 Topside Sounder Average Ionogram over Kwajalein, Marshall Islands: KWA, Latitude 9, Longitude 168 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Kwajalein/PT29S 1978-01-03T04:13:25Z 1978-12-30T21:34:08Z Spherical GEO 9 168 ISIS-1 Topside Sounder Average Ionogram over Orroral, Australia: ORR, Latitude -36, Longitude 149 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Orroral/PT29S 1970-01-28T09:47:09Z 1981-08-24T14:00:56Z Spherical GEO -36 149 ISIS-1 Topside Sounder Average Ionogram over Ottawa, QC, Canada: OTT, Latitude 45, Longitude 284 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Ottawa/PT29S 1969-01-30T14:50:12Z 1983-12-17T13:08:05Z Spherical GEO 45 284 ISIS-1 Topside Sounder Average Ionogram over Ottawa, QC, Canada, OTT, Version 2, Latitude 45, Longitude 284, 29 s Data This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Version2/Ottawa/PT29S 1969-01-30T14:50:12Z 1983-12-17T13:07:34Z Spherical GEO 45 284 ISIS-1 Topside Sounder Average Ionogram over Ouagadougou, Burkina Faso: ODG, Latitude 14, Longitude 359 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Ouagadougou/PT29S 1969-02-03T13:27:25Z 1976-06-28T17:19:36Z Spherical GEO 14 359 ISIS-1 Topside Sounder Average Ionogram over Quito, Equador: QUI, Latitude -1, Longitude 281 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Quito/PT29S 1969-01-31T04:20:04Z 1978-06-22T04:44:35Z Spherical GEO -1 281 ISIS-1 Topside Sounder Average Ionogram over Resolute Bay, NU, Canada: RES, Latitude 75, Longitude 265 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/ResoluteBay/PT29S 1969-01-30T21:18:14Z 1976-02-22T19:07:32Z Spherical GEO 75 265 ISIS-1 Topside Sounder Average Ionogram over Santiago, Chile: SNT, Latitude -33, Longitude 298 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Santiago/PT29S 1969-01-31T01:29:39Z 1972-12-25T07:01:13Z Spherical GEO -33 298 ISIS-1 Topside Sounder Average Ionogram over Sodankyla, Finland: SOD, Latitude 67, Longitude 27 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Sodankyla/PT29S 1977-12-14T22:30:46Z 1979-03-30T14:10:33Z Spherical GEO 67 27 ISIS-1 Topside Sounder Average Ionogram over Tromso, Norway: TRO, Latitude 70, Longitude 19 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Tromso/PT29S 1969-02-05T18:15:49Z 1969-12-28T15:12:00Z Spherical GEO 70 19 ISIS-1 Topside Sounder Average Ionogram over Winkfield, United Kingdom: WNK, Latitude 51, Longitude 359 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Winkfield/PT29S 1969-02-03T01:02:10Z 1975-07-18T05:06:36Z Spherical GEO 51 359 ISIS-1 Topside Sounder Average Ionogram over Quito, Equador, Version 2: QUI, Latitude -1, Longitude 281 This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Quito/Corrected/PT29S 1976-01-26T22:51:04Z 1976-07-16T10:49:12Z Spherical GEO -1 281 ISIS-1 Topside Sounder Average Ionogram over Fairbanks, AK, ULA, Version 2, Latitude 65, Longitude 212, 29 s Data This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Version2/Fairbanks/PT29S 1975-01-04T18:15:50Z 1979-09-14T12:06:02Z Spherical GEO 65 212 ISIS-1 Topside Sounder Average Ionogram over Quito, Equador, QUI, Version 2, Latitude -1, Longitude 281, 29 s Data This Ionogram was digitized from the original ISIS 1 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC. spase://NASA/NumericalData/ISIS1/SFS/AverageIonogram/Version2/Quito/PT29S 1969-01-31T04:20:04Z 1972-03-29T04:05:42Z Spherical GEO -1 281