{
  "Spase": {
    "xmlns": "http://www.spase-group.org/data/schema",
    "xmlns:xsi": "http://www.w3.org/2001/XMLSchema-instance",
    "xsi:schemaLocation": "https://www.spase-group.org/data/schema https://www.spase-group.org/data/schema/spase-2.7.1.xsd",
    "Version": "2.7.1",
    "MetadataRightsList": {
      "Rights": {
        "SchemeURI": "https://spdx.org/licenses/",
        "RightsIdentifierScheme": "SPDX",
        "RightsIdentifier": "CC0-1.0",
        "RightsURI": "https://spdx.org/licenses/CC0-1.0.html",
        "RightsName": "Creative Commons Zero v1.0 Universal",
        "Note": "CC0 1.0 Universal is the Creative Commons license applicable to all publicly available SPASE metadata descriptions"
      }
    },
    "NumericalData": {
      "ResourceID": "spase://NASA/NumericalData/THEMIS/Ground/Gakona/ASI/full_PT3S",
      "NamingAuthority": "NASA",
      "ResourceType": "NumericalData",
      "ResourceHeader": {
        "ResourceName": "Gakona THEMIS Ground-based All Sky Imager; Full Resolution Images.",
        "AlternateName": "THEMIS-Ground ASF",
        "DOI": "https://doi.org/10.48322/vpb7-yq61",
        "ReleaseDate": "2025-12-04T13:31:51Z",
        "RevisionHistory": {
          "RevisionEvent": [
            {
              "ReleaseDate": "2023-06-28T13:00:00Z",
              "Note": "Made changes requested by F. Frey, Updated version. Added contact and DOI info."
            },
            {
              "ReleaseDate": "2023-08-07T13:00:00Z",
              "Note": "Added Emma Spanswick to contacts."
            },
            {
              "ReleaseDate": "2025-08-05T13:12:40Z",
              "Note": "Added ObservedRegion(s). Changed http to https in top-level schemaLocation attribute. Fixed version number separator in top-level schemaLocation attribute. Matched version number in schemaLocation attribute to value in Version tag. ZCB"
            },
            {
              "ReleaseDate": "2025-09-30T14:25:22Z",
              "Note": "Updated PublishedBy name to match ROR Registry. Added ResourceType and NamingAuthority. ZCB"
            },
            {
              "ReleaseDate": "2025-12-04T13:31:51Z",
              "Note": "Added MetadataRightsList. Updated to 2.7.1. ZCB"
            }
          ]
        },
        "Description": "THEMIS Ground All Sky Imager at Gakona (62.39 deg GLat, 214.87 deg GLong): 256 x 256 pixel full resolution images of auroral oval.  The ASI stations monitor a 170 degree field of view imaging the auroral oval at kilometer resolution.  The ASI is comprised of a fisheye lens and CCD in a stainless steel enclosure topped with a transparent acrylic dome.  The CCD has a resolution of 256 x 256 pixels.  Exposure control ranges from 5 s to 1 ms although the typical data rate is one image every 3 seconds.  Silicone heaters keep the instrument within the nominal temperature range.  During daylight hours a sun shades deploy to protect the CCD.\n\t  ",
        "Acknowledgement": "We acknowledge NASA contract NAS5-02099 and V. Angelopoulos for use of data from the THEMIS Mission. Specifically: S. Mende and E. Donovan for use of the ASI data, and the CSA for logistical support in fielding and data retrieval from the GBO stations.",
        "PublicationInfo": {
          "Authors": "Angelopoulos, V., Mende, S. B., Donovan, E., and Frey, H. U.",
          "PublicationDate": "2023-01-01T00:00:00",
          "PublishedBy": "Space Sciences Laboratory"
        },
        "Contact": [
          {
            "PersonID": "spase://SMWG/Person/Vassilis.Angelopoulos",
            "Role": "PrincipalInvestigator"
          },
          {
            "PersonID": "spase://SMWG/Person/Stephen.B.Mende",
            "Role": "CoInvestigator"
          },
          {
            "PersonID": "spase://SMWG/Person/Eric.Donovan",
            "Role": "CoInvestigator"
          },
          {
            "PersonID": "spase://SMWG/Person/Harald.U.Frey",
            "Role": "CoInvestigator"
          },
          {
            "PersonID": "spase://SMWG/Person/Emma.Louise.Spanswick",
            "Role": "CoInvestigator"
          }
        ],
        "InformationURL": {
          "Name": "THEMIS Summary Plots",
          "URL": "http://themis.ssl.berkeley.edu/gbo/display.py?view_type=summary",
          "Description": "Summary plots containing ASI thumbnail images; useful for determining when ASI data exists."
        },
        "PriorID": [
          "spase://VMO/NumericalData/THEMIS/Ground/CANMAG/GAKO/ASI/full_PT3S",
          "spase://VSPO/NumericalData/THEMIS/Ground/Gakona/ASI/full_PT3S"
        ]
      },
      "AccessInformation": {
        "RepositoryID": "spase://SMWG/Repository/UCB/THEMIS",
        "Availability": "Online",
        "AccessRights": "Open",
        "AccessURL": {
          "Name": "THEMIS Web Data",
          "URL": "http://themis.ssl.berkeley.edu/data/themis/thg/l1/asi/gako/"
        },
        "Format": "CDF",
        "Encoding": "None"
      },
      "InstrumentID": "spase://SMWG/Instrument/THEMIS/Ground/UCLA-GBO/GAKO/ASI",
      "MeasurementType": "ImageIntensity",
      "TemporalDescription": {
        "TimeSpan": {
          "StartDate": "2006-09-12T05:00:00",
          "RelativeStopDate": "-P1Y"
        },
        "Cadence": "PT3S"
      },
      "ObservedRegion": [
        "Earth.NearSurface.Ionosphere",
        "Earth.Surface"
      ],
      "Caveats": "ASF data is retrieved by physically swapping hard drives at GBO site therefore the data is usually not available for at least 3-5 months.",
      "Parameter": [
        {
          "Name": "thg_asf_gako",
          "ParameterKey": "thg_asf_gako",
          "Description": "Full images of 256x256 pixels; saturation counts for each pixel.",
          "Units": "counts",
          "Structure": {
            "Size": "256 256"
          },
          "Wave": {
            "Qualifier": "Scalar",
            "WaveQuantity": "Intensity"
          }
        },
        {
          "Name": "thg_asf_gako_column",
          "ParameterKey": "thg_asf_gako_column",
          "Description": "Image column number; x-dimension, image width.",
          "Structure": {
            "Size": "256"
          },
          "Support": {
            "SupportQuantity": "Other"
          }
        },
        {
          "Name": "thg_asf_gako_row",
          "ParameterKey": "thg_asf_gako_row",
          "Description": "Image row number; y-dimension, image height.",
          "Structure": {
            "Size": "256"
          },
          "Support": {
            "SupportQuantity": "Other"
          }
        },
        {
          "Name": "thg_asf_gako_time",
          "ParameterKey": "thg_asf_gako_time",
          "Description": "Start of integration time, UTC, in seconds since 01-Jan-1970 00:00:00",
          "Caveats": "Not including leap seconds",
          "Units": "s",
          "ValidMin": "0.0",
          "ValidMax": "5.0E9",
          "FillValue": "NaN",
          "Support": {
            "SupportQuantity": "Temporal"
          }
        },
        {
          "Name": "thg_asf_gako_tend",
          "ParameterKey": "thg_asf_gako_tend",
          "Description": "Integration end time, UTC, in seconds since 01-Jan-1970 00:00:00",
          "Caveats": "Not including leap seconds",
          "Units": "s",
          "ValidMin": "0.0",
          "ValidMax": "5.0E9",
          "FillValue": "NaN",
          "Support": {
            "SupportQuantity": "Temporal"
          }
        }
      ]
    }
  }
}