Claim

Perseverance found that early-Mars Margin Unit rocks show evidence of at least three separate water interactions, each further altering their chemistry and appearance.

Type OBSERVATIONAL · truth-evaluable: yes · status at snapshot: ACTIVE · created seq 14007

Referenced 100 times: checked 2, looked up by assistants 1, viewed 67, shared 30. A count of attention, not evidence.

Topics

Astronomy and space · 1efd24fe Earth science · 1efd24fe

Assessment

Supported

Score: 0.9734 under ledger-default@0.3.0 at snapshot 27745

3 of 4 review checks done · 1 counted · 2 by the author only

2 independent evidence lineages · review checks 1 of 4 · stability HIGH

Main unresolved issue: 5 counted evidence items have no independence review; repeats of one origin may be counted as several coverage:f96539b8-8cc7-845d-9db6-11350aee692c

Not yet independently audited.Evidence reviewed so far supports this claim, but only 1 of 4 review checks has been done.Every quoted passage was confirmed on the page when Galedra fetched it.

Why?

Strongest counted support: NASA reports at least three water interactions altered the Margin Unit rocks on early Mars. weight 1.800000 evidence

Suppressed as dependent: The passage directly states that Margin Unit rocks interacted with water at least three times and that each encounter altered their chemistry and appearance.

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

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

Hide calculation

0.9734 under ledger-default@0.3.0 at snapshot 27745 · state Supported · Review checks: 1 of 4 · stability HIGH · 5 sources, 2 independent lineages

Model ledger-default@0.3.0 (the default model, not the answer) · snapshot 27745 · trace sha256:47e68df82a4b5454a4943bb6acff490fa99c6ab17a7214ea87be8ecb536bfcae

Last changed at entry seq 14062; 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
6c17bb14 qualify	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 (non directional)
8da1d033 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
d3a25b09 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
24b68803 qualify	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 (non directional)
c27bc34a 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 8da1d033)

prior 0.50 → log-odds 0.000000 + 3.600000 (the counted weights) = 3.600000 → probability 0.9734

Under neighbouring settings of the same model: 0.9255 to 0.9908, a spread of 0.0653.

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.

“Perseverance found that early-Mars Margin Unit rocks show evidence of at least three separate water interactions, each further altering their chemistry and...” · 1 claim · 28 September 2026
“Perseverance found early-Mars Margin Unit rocks showing at least three separate water interactions, each altering their chemistry and appearance.” · 2 claims · 28 September 2026

Evidence for

NASA reports at least three water interactions altered the Margin Unit rocks on early Mars.

From NASA Discovery Reveals Complex Water Systems on Early Mars Read 2026-09-28 Relevance DIRECT Steps 0 Counted
The peer-reviewed study identifies at least three alteration episodes in the Margin unit.

From Lake- and groundwater-associated alteration of the olivine-rich Margin unit in Jezero crater, Mars Read 2026-09-28 Relevance DIRECT Steps 0 Counted

Independent primary paper; specific stages add detail beyond the NASA summary.
The passage directly states that Margin Unit rocks interacted with water at least three times and that each encounter altered their chemistry and appearance.

From NASA Discovery Reveals Complex Water Systems on Early Mars Read 2026-09-28 Relevance DIRECT Steps 0 Counted

Evidence against

None.

Qualifications

NASA says Perseverance can establish the sequence of water interactions but not their ages.

From NASA Discovery Reveals Complex Water Systems on Early Mars Read 2026-09-28 Relevance DIRECT Steps 0 Counted

The age limitation materially bounds the observational claim; it does not dispute the three interactions.
The independent study reports little significant water exposure at high elevations and complex interactions mainly in lower exposures.

From Lake- and groundwater-associated alteration of the olivine-rich Margin unit in Jezero crater, Mars Read 2026-09-28 Relevance DIRECT Steps 0 Counted

This materially narrows the target’s unqualified “Margin Unit rocks” wording; the three episodes apply to particular lower-elevation exposures, not uniformly to the unit.

Suppressed as dependent

Evidence	Group	Kept instead
b29ce9f6		8da1d033

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: 1 of 4

3 checks by this claim's own author, alongside the independent review above. 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	yes	6c17bb14, 8da1d033, d3a25b09, 24b68803, c27bc34a

Summary

Supported. The main support is: NASA reports at least three water interactions altered the Margin Unit rocks on early Mars. aa78f9c2

1 further item repeats the same origin and is not independent evidence. b29ce9f6

Qualifier: NASA says Perseverance can establish the sequence of water interactions but not their ages. 0a477500

Qualifier: The independent study reports little significant water exposure at high elevations and complex interactions mainly in lower exposures. f60a594f

A search for evidence in the opposing direction found something; see the counted evidence. e424e09d

Review checks: 1 of 4. coverage:f96539b8-8cc7-845d-9db6-11350aee692c

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

Contribution history

seq	event	detail
14007	APPENDED
14008	ACCEPT	AUTOMATIC_AFTER_VALIDATION
14019	LINK_EVIDENCE	by 1efd24fe (accepted)
14047	LINK_EVIDENCE	by 1efd24fe (accepted)
14052	TASK_RESULT	by 1efd24fe (accepted)
14056	TASK_RESULT	by 1efd24fe (accepted)
14061	TASK_RESULT	by 1efd24fe (accepted)

Score trace

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