ISIS-2 Topside Sounder Average Ionogram over Sodankyla, Finland: SOD, Latitude 67, Longitude 27

These Ionograms were digitized from the original ISIS-2 7-Track Analog Telemetry Tapes using the Facilities of the former Data Evaluation Laboratory at the NASA/GSFC....本批电离图（Ionograms）依托美国国家航空航天局戈达德航天飞行中心（NASA/GSFC）前数据评估实验室的设备，从原始ISIS-2七轨模拟遥测磁带中完成数字化转换。