{
  "schemaVersion": 1,
  "preparedAtUTC": "2026-10-16T20:40:11.080Z",
  "purpose": "Registered, measured selected-band structure for an aesthetic celestial background and future scalar inspection.",
  "truthBoundary": "Historic Planck 857 GHz intensity mapped to visible false color. Not a full-spectrum photograph, live observation, calibrated composite, literal human-visible sky or newly inferred physics.",
  "coordinateFrame": "ICRS",
  "projection": "CAR (plate carree)",
  "width": 2048,
  "height": 1024,
  "exportWcs": {
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    "NAXIS1": 2048,
    "NAXIS2": 1024,
    "CRPIX1": 1024.5,
    "CRPIX2": 512.5,
    "CDELT1": -0.17578125,
    "CDELT2": 0.17578125,
    "CUNIT1": "deg",
    "CUNIT2": "deg",
    "CTYPE1": "RA---CAR",
    "CTYPE2": "DEC--CAR",
    "CRVAL1": 0,
    "CRVAL2": 0,
    "RADESYS": "ICRS"
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  "imageOrientation": {
    "rows": "north to south",
    "columns": "RA increases to the left",
    "center": "RA=0 degrees, Dec=0 degrees lies between central pixels",
    "pixelCenterFormula": {
      "ra": "mod(180 - (x + 0.5) * 360 / width, 360)",
      "dec": "90 - (y + 0.5) * 180 / height"
    },
    "edges": "left RA=180 deg, right RA=-180/180 deg; top Dec=90 deg, bottom Dec=-90 deg; pixel centers avoid the poles and seam"
  },
  "samplePolicy": "Float grids preserve physical units and real zeros; absent samples are NaN plus mask=0. Average only valid samples. Do not infer observation precision from float32 storage.",
  "processing": {
    "script": "scripts/prepare-multiband-fusion.mjs",
    "runtime": "v26.4.0",
    "sourceReprojection": "CDS HiPS2FITS, explicit ICRS CAR WCS from each named scalar HiPS",
    "sourceFitsBytePreserved": true,
    "sourceFitsStorage": "Raw response is not redistributed in the public package. Original bytes can be retained in an explicitly selected private source cache; export URL and SHA-256 are always recorded.",
    "colorizer": "recorded per-band clipped-percentile asinh transfer and interpolated RGB stops",
    "smoothing": "none added",
    "fabricatedData": false,
    "interBandFusion": "none; renderers may blend layers aesthetically but must not claim physical calibration between bands"
  },
  "acknowledgment": "Uses ESA and the Planck Collaboration frequency maps, CDS/CNRS/Unistra HiPS and CDS HiPS2FITS.",
  "rejectedSources": [
    {
      "researchAuditDateUTC": "2026-10-16",
      "hips": "ov-gso/P/IRIS/4",
      "band": "IRIS 100 micrometres",
      "propertiesUrl": "https://cade.irap.omp.eu/documents/Ancillary/4Aladin/IRIS_04/properties",
      "status": "Rejected before derivative generation",
      "reason": "The 2048x1024 ICRS CAR scalar export mixed the finite -32768 missing-data sentinel with valid samples (observed minimum excluding exact sentinel: -32767.640625). No arbitrary threshold, invented hole filling or physical-value claim was substituted."
    },
    {
      "researchAuditDateUTC": "2026-10-16",
      "hips": "ov-gso/P/RASS",
      "band": "ROSAT 0.1-2.4 keV",
      "status": "Excluded from public assets",
      "reason": "CADE scalar HiPS declares IRAP/CADE copyright without an explicit reuse license. Survey scan artifacts are also prominent. Candidate data and source captures are kept privately rather than redistributed.",
      "numericStudy": {
        "sourceZeros": 3919,
        "positiveExposureZerosRetained": 2169,
        "nonpositiveExposurePixelsExcluded": 1750
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      "alternative": {
        "hips": "CDS/P/RASS",
        "license": "ODbL-1.0",
        "status": "Not substituted: 16-bit properties do not establish equivalent physical units/calibration."
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  ],
  "references": [
    "https://alasky.cds.unistra.fr/hips-image-services/hips2fits",
    "https://irsa.ipac.caltech.edu/data/Planck/release_3/all-sky-maps/",
    "https://opendatacommons.org/licenses/odbl/1-0/"
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  "bands": [
    {
      "key": "infrared",
      "slug": "infrared-planck857",
      "hips": "CDS/P/PLANCK/R3/HFI857",
      "title": "Planck PR3 HFI 857 GHz intensity",
      "unit": "MJy/sr",
      "sourceSentinels": [],
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      "sourcePage": "https://irsa.ipac.caltech.edu/data/Planck/release_3/all-sky-maps/",
      "providerPage": "https://www.cosmos.esa.int/web/planck/pla",
      "reference": "https://doi.org/10.1051/0004-6361/201833880",
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      "angularResolutionArcminutes": 4.6,
      "sourceDescription": "Historic full-mission Planck HFI map from the 2018 PR3 release; HFI operations ended January 2012. Not a live sky.",
      "palette": {
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      "credits": [
        "ESA and the Planck Collaboration; Planck 2018 results I, A&A 641, A1",
        "Planck Legacy Archive; CDS/CNRS/Unistra HiPS by Buga M.; CDS HiPS2FITS reprojection"
      ],
      "quality": {
        "status": "SOURCE_AND_NUMERIC_PASS",
        "acceptedForDefaultBackground": true,
        "limitations": [
          "Local source/coordinate/numeric/image verification only; page rendering and device acceptance remain separate."
        ]
      },
      "caveats": [
        "This is the Stokes-I frequency-map intensity, not a pure dust, CMB, temperature or polarization component.",
        "MJy/sr follows the Planck convention of a constant nu F_nu energy distribution; do not silently apply a different bandpass/color correction.",
        "Display colors encode measured intensity in one unseen frequency channel, not the light a human eye would see."
      ],
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        "hips": "CDS/P/PLANCK/R3/HFI857",
        "service": "https://alasky.cds.unistra.fr/PLANCK/R3/HFI_SkyMap_857_R3",
        "propertiesUrl": "https://alasky.cds.unistra.fr/PLANCK/R3/HFI_SkyMap_857_R3/properties",
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          "hips_initial_dec": "+0",
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          "hips_creator": "Buga M. (CDS)",
          "hips_copyright": "CNRS/Unistra",
          "hips_license": "ODbL-1.0",
          "obs_title": "PLANCK R3 frequency HFI map 857 GHz",
          "obs_collection": "PLANCK R3 HFI 857 GHz",
          "obs_description": "Planck is ESA's mission to observe the first light in the Universe. Planck was launched on 14 May 2009, and the minimum requirement for success was for the spacecraft to complete two whole surveys of the sky. In the end, Planck worked perfectly for 30 months, about twice the span originally required, and completed five full-sky surveys with both instruments. Able to work at slightly higher temperatures than HFI, the Low Frequency Instrument (LFI) continued to survey the sky for a large part of 2013, providing even more data to improve the Planck final results. Planck was turned off on 23 October 2013. The high-quality data the mission has produced will continue to be scientifically explored in the years to come.",
          "obs_ack": "ESA and the Planck Collaboration",
          "prov_progenitor": "ESA",
          "bib_reference": "2020A&A...641A...1P",
          "bib_reference_url": "https://ui.adsabs.harvard.edu/abs/2020A%26A...641A...1P/abstract",
          "obs_copyright": "EUROPEAN SPACE AGENCY. ALL RIGHTS RESERVED",
          "obs_copyright_url": "https://www.cosmos.esa.int/web/planck",
          "t_min": "55054.9166667",
          "t_max": "56587.9166667",
          "obs_regime": "Radio",
          "em_min": "0.0003498161703617",
          "em_max": "0.0003498161703617",
          "client_category": "Image/Radio/PLANCK/R3/HFI",
          "hips_builder": "Aladin/HipsGen v12.013",
          "hips_version": "1.4",
          "hips_release_date": "2022-10-26T10:18Z",
          "hips_frame": "galactic",
          "hips_order": "3",
          "hips_order_min": "0",
          "hips_tile_width": "256",
          "hips_status": "public master clonableOnce",
          "hips_tile_format": "png fits",
          "hips_pixel_bitpix": "-32",
          "hips_pixel_cut": "0.4803 469.8",
          "hips_data_range": "-3834 11505",
          "hips_pixel_scale": "0.02863",
          "dataproduct_type": "image",
          "hipsgen_date": "2022-10-26T10:17Z",
          "hipsgen_params": "in=../../Frequency-maps_Single-frequency/HFI_SkyMap_857_2048_R3.01_full.fits out=HiPS_HFI_SkyMap_857/ creator_did=CDS/P/PLANCK/R3/HFI857",
          "hips_creation_date": "2022-10-26T10:17Z",
          "hips_estsize": "291476",
          "hips_nb_tiles": "2042",
          "hips_check_code": "png:3351337634 fits:269935101"
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          "CPYRIGHT": "EUROPEAN SPACE AGENCY. ALL RIGHTS RESERVED - &"
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      },
      "rights": {
        "copyright": "EUROPEAN SPACE AGENCY. ALL RIGHTS RESERVED",
        "hipsCopyright": "CNRS/Unistra",
        "licenseIdentifier": "ODbL-1.0",
        "licenseUrl": "https://opendatacommons.org/licenses/odbl/1-0/",
        "status": "The CDS HiPS metadata explicitly declares ODbL-1.0. Retain source and provider attribution, source rights notices, and this license link with the database and produced visualization.",
        "acknowledgmentSource": "https://www.cosmos.esa.int/web/planck/publications"
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        "realZeroIsValid": true,
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        "maskMeaning": "Numeric validity after documented non-finite/sentinel exclusion, not an uncertainty assessment.",
        "physicalGridMissing": "IEEE NaN plus explicit mask=0",
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        "samplesPerCell": 16,
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        "caution": "A display-resolution resampling, not an equal-area statistic, aperture flux, uncertainty estimate or replacement for original survey analysis."
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          "quantization": "The unchanged scalar transfer and palette precede rounding to 8-bit RGB; no lossy codec stage.",
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            "licenseIdentifier": "ODbL-1.0",
            "licenseUrl": "https://opendatacommons.org/licenses/odbl/1-0/",
            "status": "The CDS HiPS metadata explicitly declares ODbL-1.0. Retain source and provider attribution, source rights notices, and this license link with the database and produced visualization.",
            "acknowledgmentSource": "https://www.cosmos.esa.int/web/planck/publications"
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  "updatedAtUTC": "2026-10-16T21:17:10.737Z"
}