{
 "kind": "spacecraft_field_measurements",
 "date": "2026-09-16",
 "built_utc": "2026-09-16T09:04:29+00:00",
 "rows": 13,
 "bytes": 26257,
 "sha256": "5cf6e96f8f4b63fa19646cc4ec5f7a1fb4f2b341c618157e5fa69afa5eb82d1c",
 "columns": [
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   "name": "slot_id",
   "dtype": "String"
  },
  {
   "name": "kind",
   "dtype": "String"
  },
  {
   "name": "name",
   "dtype": "String"
  },
  {
   "name": "start_utc",
   "dtype": "String"
  },
  {
   "name": "end_utc",
   "dtype": "String"
  },
  {
   "name": "lat",
   "dtype": "Float64"
  },
  {
   "name": "lon",
   "dtype": "Float64"
  },
  {
   "name": "n_obs",
   "dtype": "Float64"
  },
  {
   "name": "spacecraft",
   "dtype": "String"
  },
  {
   "name": "instrument",
   "dtype": "String"
  },
  {
   "name": "launch_utc",
   "dtype": "String"
  },
  {
   "name": "nssdca_dataset_id",
   "dtype": "String"
  },
  {
   "name": "n_readings_full",
   "dtype": "Float64"
  }
 ],
 "slot_id_column": "slot_id",
 "time_column": "start_utc",
 "sorted_by": [
  "start_utc",
  "slot_id"
 ],
 "row_groups": "one per year",
 "span": {
  "start": "1961-08-16T05:10:09.208000+00:00",
  "end": "1966-07-01T17:34:20.113225+00:00"
 },
 "source_file": "platform_storehouse/spacecraft_field_measurements/_manifest.parquet",
 "url": "https://data.terrapulse.info/dex/spacecraft_field_measurements/2026-09-16.parquet",
 "latest_url": "https://data.terrapulse.info/dex/spacecraft_field_measurements/latest.parquet",
 "family": "movingplatformdex",
 "storage": "dossier",
 "n_slots_api": 13,
 "sources": [
  "spdf_explorer12_mag",
  "spdf_mariner2",
  "spdf_explorer18_mag",
  "spdf_explorer21_mag",
  "spdf_mariner4_mag",
  "spdf_explorer28_mag",
  "spdf_ogo2_mag",
  "spdf_pioneer6_mag30s",
  "spdf_pioneer6_maghr",
  "spdf_ogo3_searchcoil",
  "spdf_explorer33_gsfc_mag",
  "spdf_explorer33_ames_mag"
 ],
 "licence_basis": "NASA SPDF open-data archive (Rules of the Road: freely available, no use restriction; acknowledgment requested). US government missions (Explorer 12, Mariner 2, Explorer 18, Explorer 21, Mariner 4, Explorer 28, OGO 2, Pioneer 6, OGO 3, Explorer 33); recovered NSSDC archive hosted by NASA.",
 "commercial_use": true,
 "cite": "TerraPulse (terrapulse.info) for the organizing; the sources above for the measurements, as their licence requires."
}