{
 "kind": "spacecraft_field_measurements",
 "date": "2026-09-19",
 "built_utc": "2026-09-19T09:02:48+00:00",
 "rows": 28,
 "bytes": 36413,
 "sha256": "87910a3f00626d89afb0c59af77740272b707b363657fed7dd073c746cfe2c8d",
 "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": [
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 ],
 "row_groups": "one per year",
 "span": {
  "start": "1961-08-16T05:10:09.208000+00:00",
  "end": "1968-03-12T23:55:38+00:00"
 },
 "source_file": "platform_storehouse/spacecraft_field_measurements/_manifest.parquet",
 "url": "https://data.terrapulse.info/dex/spacecraft_field_measurements/2026-09-19.parquet",
 "latest_url": "https://data.terrapulse.info/dex/spacecraft_field_measurements/latest.parquet",
 "family": "movingplatformdex",
 "storage": "dossier",
 "n_slots_api": 28,
 "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",
  "spdf_pioneer7_mag30s",
  "spdf_pioneer7_maghr",
  "spdf_ats1_mag15s",
  "spdf_ats1_mag2p5",
  "spdf_ariel3_hf_noise",
  "spdf_imp4_mag25",
  "spdf_imp4_mag20",
  "spdf_explorer35_gsfc_mag82",
  "spdf_explorer35_ames_mag5",
  "spdf_ogo4_mag",
  "spdf_ogo5_fg4",
  "spdf_ogo5_fg1m_gsm",
  "spdf_ogo5_fg_highrate",
  "spdf_ogo5_searchcoil",
  "spdf_ogo5_plasma_wave"
 ],
 "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, Pioneer 7, ATS 1, IMP 4, Explorer 35); recovered NSSDC archive hosted by NASA. Ariel 3 (UK, Radio and Space Research Station): the experimenter's tapes deposited at NSSDC and served by SPDF on the same terms; measured facts, not expression.",
 "commercial_use": true,
 "cite": "TerraPulse (terrapulse.info) for the organizing; the sources above for the measurements, as their licence requires."
}