{
  "note": "Maximum sustainable biomass per environment (kg C). Earth is a MEASURED census; every other value is a MODELLED theoretical ceiling spanning orders of magnitude — never a measurement. Mars has no defensible planet-total. % is of Earth's total biomass.",
  "generatedAt": "2026-06-16",
  "earthBiomassKgC": 550000000000000000,
  "bodies": 4,
  "table": {
    "EARTH": {
      "depth": "both",
      "bestKgC": 550000000000000000,
      "lowKgC": 400000000000000000,
      "highKgC": 700000000000000000,
      "confidence": "measured",
      "note": "measured census; ~85% surface, ~15% deep subsurface (~8×10¹⁶ kg C)",
      "source": "Bar-On, Phillips & Milo 2018, PNAS; Magnabosco et al. 2018, Nat. Geosci.",
      "pctEarth": 100
    },
    "ENCELADUS": {
      "depth": "subsurface",
      "bestKgC": 10000,
      "lowKgC": 100,
      "highKgC": 10000000,
      "confidence": "modelled",
      "note": "best-constrained off-Earth: a methanogenic ocean biosphere from the Cassini H₂/CH₄ flux — a few tons of C",
      "source": "Affholder et al. 2021, Nat. Astron.; Higgins et al. 2024, JGR Planets",
      "pctEarth": 1.8181818181818183e-12
    },
    "EUROPA": {
      "depth": "subsurface",
      "bestKgC": 1000000,
      "lowKgC": 10000,
      "highKgC": 10000000,
      "confidence": "modelled",
      "note": "steady-state cells from crustal recycling; serpentinization/oxidant-limited (wide uncertainty)",
      "source": "Chyba & Phillips 2001, PNAS",
      "pctEarth": 1.8181818181818182e-10
    },
    "MARS": {
      "depth": "subsurface",
      "bestKgC": null,
      "confidence": "modelled",
      "note": "no published planet-total; radiolytic deep biosphere ~10⁶ cells/kg rock (Earth-deep-subsurface-like)",
      "source": "Tarnas et al. 2018, EPSL; 2021, Astrobiology",
      "pctEarth": null
    }
  }
}