Claim

NASA reported that Webb observations of the gas giant WD 1856 b detected methane signatures in its atmosphere while it orbited a white dwarf.

Type OBSERVATIONAL · truth-evaluable: yes · status at snapshot: ACTIVE · created seq 13057

Referenced 102 times: checked 2, looked up by assistants 0, viewed 71, shared 29. A count of attention, not evidence.

Topics

Astronomy and space · 1efd24fe Chemistry · 1efd24fe

Assessment

Supported

Score: 0.9781 under ledger-default@0.3.0 at snapshot 27745

2 of 4 review checks done · 0 counted · 2 by the author only

2 independent evidence lineages · review checks 0 of 4 · stability HIGH

Main unresolved issue: 3 counted evidence items have no independence review; repeats of one origin may be counted as several coverage:1e08d346-d69f-86c9-82d8-2921695a0dec

Not yet independently audited.Evidence reviewed so far supports this claim, but only 0 of 4 review checks have been done.A quoted passage from science.nasa.gov was not found on the page when Galedra fetched it.

Why?

Strongest counted support: NASA reports methane-like hydrocarbon signatures in WD 1856 b's atmosphere during transit of a white dwarf. weight 2.000000 evidence

Suppressed as dependent: The passage directly reports likely methane hydrocarbon signatures in an atmosphere on a planet transiting a white dwarf.

Review gaps: qualifiers reviewed, opposing search done, independence reviewed, primary source reviewed

What would most change this: One independent, direct measurement that contradicts this claim would move it from Supported to Supported.

Hide calculation

0.9781 under ledger-default@0.3.0 at snapshot 27745 · state Supported · Review checks: 0 of 4 · stability HIGH · 3 sources, 2 independent lineages

Model ledger-default@0.3.0 (the default model, not the answer) · snapshot 27745 · trace sha256:db5be3cb1afb9e6c8a38021072689958daa42db356114814fbbc5cb88942ca61

Last changed at entry seq 13362; nothing logged since has borne on this claim.

How the number was reached

Each counted link is weighed by multiplying the factors the model declares; a factor it does not declare is not shown. Every factor name below links to what that number means.

Link	Working	Weight	Counted as
ce2844f8 support	relevance DIRECT 2.0 × observation DIRECT_TEXT 0.9 × interpretation 0 steps, 1 − 0.15 × 0 1.000000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	1.800000	1.800000
e03e0055 support	relevance DIRECT 2.0 × observation MEASUREMENT 1.0 × interpretation 0 steps, 1 − 0.15 × 0 1.000000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	2.000000	2.000000
c1f0b4c5 support	relevance DIRECT 2.0 × observation DIRECT_TEXT 0.9 × interpretation 0 steps, 1 − 0.15 × 0 1.000000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	1.800000	0.000000 (dependent strongest only, kept e03e0055)

prior 0.50 → log-odds 0.000000 + 3.800000 (the counted weights) = 3.800000 → probability 0.9781

Under neighbouring settings of the same model: 0.9346 to 0.9929, a spread of 0.0583.

Half-even rounding, six places for weights and four for the probability. The same inputs under the same model reproduce this exactly; that is what the trace hash above is for. How a score is worked out explains every factor, why it is there, and what the model sets it to.

Your view

Registered views

Nobody has registered a view yet.

Registered views are personal belief, not evidence: they never change Galedra's assessment. Affiliations are self-declared and shown only for groups of 5 or more.

Checked as part of

Statements this claim was broken out of. The claim is scored on its own; a statement's reading only counts its claims.

“NASA reported that Webb observations of the gas giant WD 1856 b detected methane signatures in its atmosphere while it orbited a white dwarf.” · 1 claim · 28 September 2026
“NASA reported that Webb observations of the gas giant WD 1856 b detected methane signatures in its atmosphere while it orbited a white dwarf.” · 1 claim · 28 September 2026

Evidence for

NASA reports methane-like hydrocarbon signatures in WD 1856 b's atmosphere during transit of a white dwarf.

From NASA’s Webb Studies How Planet Survived Death of its Star Read 2026-09-28 Relevance DIRECT Steps 0 Counted

NASA's mission report directly attributes the atmospheric signature to Webb observations.
NASA's Webb transmission-spectrum asset says WD 1856 b's atmosphere shows signs of methane.

From Exoplanet WD 1856 b (Transmission Spectrum) Read 2026-09-28 Relevance DIRECT Steps 0 Counted

Official NASA asset independently states the methane finding.
The passage directly reports likely methane hydrocarbon signatures in an atmosphere on a planet transiting a white dwarf.

From NASA’s Webb Studies How Planet Survived Death of its Star Read 2026-09-28 Relevance DIRECT Steps 0 Counted

Evidence against

None.

Qualifications

None.

Suppressed as dependent

Evidence	Group	Kept instead
c6493e22		e03e0055

Inferences

Concluded from

None.

Used as a premise in

None.

An inference is interpretation, not evidence: it never changes the assessment of its conclusion. Each premise is a claim with its own evidence.

Threads

None. Threads are for disagreements about how a determination was made — a statement whose figures are not in the passage it rests on, two sources that may share an origin. Something about the world belongs in the evidence above.

Claim edges

None. Edges are stored and displayed; v0.1 does not propagate probability across them.

Review checklist

Review checks: 0 of 4

3 checks by this claim's own author. No independent review yet. 1 OPPOSING EVIDENCE SEARCH · 1 QUALIFIER CHECK · 1 EVIDENCE VERIFICATION. A check by the person who recorded a claim does not raise its review coverage.

Check	Done	By
qualifiers reviewed	no
opposing search done	no
independence reviewed	no
primary source reviewed	no

Summary

Supported. The main support is: NASA's Webb transmission-spectrum asset says WD 1856 b's atmosphere shows signs of methane. b878877c

1 further item repeats the same origin and is not independent evidence. c6493e22

A search for evidence in the opposing direction found none. 76e19b2a

Review checks: 0 of 4. coverage:1e08d346-d69f-86c9-82d8-2921695a0dec

Generated by stub-v0.1; every sentence cites graph ids.

Contribution history

seq	event	detail
13057	APPENDED
13058	ACCEPT	AUTOMATIC_AFTER_VALIDATION
13063	LINK_EVIDENCE	by 1efd24fe (accepted)
13074	LINK_EVIDENCE	by 1efd24fe (accepted)
13076	TASK_RESULT	by 1efd24fe (accepted)

Score trace

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  "claim": "1e08d346-d69f-86c9-82d8-2921695a0dec",
  "links": [
    {
      "link": "39a675bc-9779-8acd-8da7-246ace2844f8",
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      "direction": "SUPPORT",
      "magnitude": "1.800000",
      "relevance": "DIRECT",
      "extraction": "UNVERIFIED",
      "provenance": "INDEPENDENT",
      "observation": "DIRECT_TEXT",
      "source_type": "WEBSITE",
      "authenticity": "UNVERIFIED",
      "audit_confirmed": false,
      "effective_weight": "1.800000",
      "interpretive_steps": 0
    },
    {
      "link": "ee4b5000-5d19-87af-b709-ee9ce03e0055",
      "group": null,
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      "direction": "SUPPORT",
      "magnitude": "2.000000",
      "relevance": "DIRECT",
      "extraction": "UNVERIFIED",
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      "observation": "MEASUREMENT",
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    },
    {
      "kept": "ee4b5000-5d19-87af-b709-ee9ce03e0055",
      "link": "f004a311-efba-89a7-b115-651dc1f0b4c5",
      "group": null,
      "reason": "dependent_strongest_only",
      "edition": "NAMED_OR_UNRELATED",
      "evidence": "00121866-f837-859f-9c2c-c2dac6493e22",
      "direction": "SUPPORT",
      "magnitude": "1.800000",
      "relevance": "DIRECT",
      "extraction": "UNVERIFIED",
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      "authenticity": "UNVERIFIED",
      "audit_confirmed": false,
      "effective_weight": "0.000000",
      "interpretive_steps": 0
    }
  ],
  "model": "ledger-default@0.3.0",
  "prior": "0.50",
  "variants": {
    "spread": "0.0583",
    "permissive": "0.9929",
    "conservative": "0.9346"
  },
  "code_hash": "sha256:c61a6fdf35a754a0d7e958df149036a083c0eaeb7d2d2e52704ec32b0c36def7",
  "contested": false,
  "stability": "HIGH",
  "claim_type": "OBSERVATIONAL",
  "config_hash": "sha256:86768038080b8ab5233f1e4b7aba10af05b5bb44caa432095150b90e81209809",
  "probability": "0.9781",
  "provisional": true,
  "evidence_sum": "3.800000",
  "snapshot_seq": 13362,
  "prior_log_odds": "0.000000",
  "support_groups": 2,
  "model_dependent": false,
  "review_coverage": "0.00",
  "truth_evaluable": true,
  "assessment_state": "SUPPORTED",
  "review_checklist": {
    "qualifiers_reviewed": {
      "by": [],
      "ok": false
    },
    "opposing_search_done": {
      "by": [],
      "ok": false
    },
    "independence_reviewed": {
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      "ok": false
    },
    "primary_source_reviewed": {
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      "ok": false
    }
  },
  "contradict_groups": 0,
  "rounding_boundary": false,
  "posterior_log_odds": "3.800000",
  "not_applicable_reason": null,
  "independence_unreviewed": 3
}