Claim

The Great Wall of China is visible from space with the naked eye.

Type OBSERVATIONAL · truth-evaluable: yes · status at snapshot: ACTIVE · created seq 246

Referenced 224 times: checked 2, looked up by assistants 0, viewed 122, shared 100. A count of attention, not evidence.

Topics

Astronomy and space · d6193340

Assessment

Contradicted

Score: 0.0028 under ledger-default@0.3.0 at snapshot 27745

3 of 4 review checks done · 3 counted

6 independent evidence lineages · review checks 3 of 4 · stability HIGH

Main unresolved issue: 8 counted evidence items have no independence review; repeats of one origin may be counted as several coverage:6c02104e-b1db-8e2a-af16-74610c1928ca

Not yet independently audited; some evidence was recorded by an anonymous contributor.Evidence points both ways.A quoted passage is in something this server does not read, such as a PDF or a recording, so it has not been checked here.

Why?

Strongest counted support: Scientific American reports that astronauts Eugene Cernan and Ed Lu said they saw the Great Wall from low orbit, under certain lighting conditions. weight 0.459000 evidence

Strongest counted contradiction: NASA states that the Great Wall generally is not visible to the unaided eye in low Earth orbit and is not visible from the Moon. weight 1.800000 evidence

Suppressed as dependent: The excerpt states that the Great Wall is not visible to the naked eye from orbit, directly contradicting the claim that it is visible with the naked eye from space.

Review gaps: independence reviewed

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

Hide calculation

0.0028 under ledger-default@0.3.0 at snapshot 27745 · state Contradicted · Review checks: 3 of 4 · stability HIGH · 8 sources, 6 independent lineages

Model ledger-default@0.3.0 (the default model, not the answer) · snapshot 27745 · trace sha256:3ff59a0fdc631f081deee303fbb159fbd9ca7cfdb364948d89e6366ddace71d6

Last changed at entry seq 11597; 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
159d009e contradict	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
99908812 contradict	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
8c87afc4 contradict	relevance STRONG 1.2 × 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	1.080000	1.080000
03eaa224 support	relevance MODERATE 0.6 × observation EXPERT_ANALYSIS 0.3 × interpretation 1 step, 1 − 0.15 × 1 0.850000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	0.153000	0.153000
457f3f0b support	relevance MODERATE 0.6 × observation DIRECT_TEXT 0.9 × interpretation 1 step, 1 − 0.15 × 1 0.850000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	0.459000	0.459000
1fc0b11e qualify	relevance STRONG 1.2 × observation EXPERT_ANALYSIS 0.3 × interpretation 1 step, 1 − 0.15 × 1 0.850000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	0.306000	0.000000 (non directional)
b0523f38 contradict	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
285e373d contradict	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 b0523f38)

prior 0.50 → log-odds 0.000000 + -5.868000 (the counted weights) = -5.868000 → probability 0.0028

Under neighbouring settings of the same model: 0.0162 to 0.0005, a spread of 0.0157.

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.

“The Great Wall of China is visible from space with the naked eye.” · 1 claim · 28 September 2026
“The Great Wall of China is visible from space with the naked eye.” · 1 claim · 28 September 2026
“FACT CHECK YOUR TEACHERS 🧠 Humans only use 10% of their brains. Einstein failed math as a kid and still changed physics. The Great Wall of China is the only...” · 8 claims · 19 September 2026

Evidence for

Scientific American reports that astronauts Eugene Cernan and Ed Lu said they had seen the Great Wall from low Earth orbit.

From Is China's Great Wall Visible from Space? Read 2026-09-18 Relevance MODERATE Steps 1 Counted

Supports possible naked-eye visibility from low Earth orbit based on reported astronaut observations.
Scientific American reports that astronauts Eugene Cernan and Ed Lu said they saw the Great Wall from low orbit, under certain lighting conditions.

From Is China's Great Wall Visible from Space? Read 2026-09-28 Relevance MODERATE Steps 1 Counted

The source supports visibility from low orbit but qualifies it by lighting conditions and conflicts with other astronaut accounts.

Evidence against

NASA states that the Great Wall is not visible to the naked eye from orbit.

From NASA Earth Science and Remote Sensing Unit FAQ Read 2026-09-18 Relevance DIRECT Steps 0 Counted

Directly contradicts unaided visibility from orbit.
ESA astronaut Alexander Gerst described seeing the Great Wall from the ISS with the naked eye as next to impossible and used an 800 mm telephoto lens.

From Great Wall of China Read 2026-09-18 Relevance STRONG Steps 0 Counted

An ISS astronaut says naked-eye visibility is next to impossible and resorted to a telephoto lens.
The excerpt states that the Great Wall is not visible to the naked eye from orbit, directly contradicting the claim that it is visible with the naked eye from space.

From NASA Earth Science and Remote Sensing Unit FAQ Read 2026-09-18 Relevance DIRECT Steps 0 Counted
NASA says the Great Wall is difficult or impossible to see from Earth orbit without high-powered lenses, directly contradicting naked-eye visibility.

From Great Wall Read 2026-09-28 Relevance DIRECT Steps 0 Counted

NASA's page describes the ISS photograph and distinguishes camera-assisted imagery from unaided visibility.
NASA states that the Great Wall generally is not visible to the unaided eye in low Earth orbit and is not visible from the Moon.

From China’s Wall Less Great in View from Space Read 2026-09-28 Relevance DIRECT Steps 0 Counted

Directly contradicts the claim that the Great Wall is visible from space with the naked eye.

Qualifications

Scientific American reports that any such visibility from low orbit depends on particular lighting conditions.

From Is China's Great Wall Visible from Space? Read 2026-09-18 Relevance STRONG Steps 1 Counted

Limits any low-orbit visibility to special lighting conditions rather than ordinary viewing.

Suppressed as dependent

Evidence	Group	Kept instead
414b482f		b0523f38

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: 3 of 4

Check	Done	By
qualifiers reviewed	yes	113f19d2
opposing search done	yes	685a7ff5
independence reviewed	no
primary source reviewed	yes	159d009e

Summary

Contradicted. The main support is: Scientific American reports that astronauts Eugene Cernan and Ed Lu said they had seen the Great Wall from low Earth orbit. 2440c8b5

Against that, contradiction: NASA states that the Great Wall generally is not visible to the unaided eye in low Earth orbit and is not visible from the Moon. 500faa72

1 further item repeats the same origin and is not independent evidence. 414b482f

Qualifier: Scientific American reports that any such visibility from low orbit depends on particular lighting conditions. e15aec33

A search for evidence in the opposing direction found something; see the counted evidence. 685a7ff5

Review checks: 3 of 4. coverage:6c02104e-b1db-8e2a-af16-74610c1928ca

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

Contribution history

seq	event	detail
246	APPENDED
247	ACCEPT	AUTOMATIC_AFTER_VALIDATION
256	LINK_EVIDENCE	by e02a4612 (accepted)
258	LINK_EVIDENCE	by e02a4612 (accepted)
260	LINK_EVIDENCE	by e02a4612 (accepted)
262	LINK_EVIDENCE	by e02a4612 (accepted)
8936	TASK_RESULT	by 1efd24fe (accepted)
11205	TASK_RESULT	by 1efd24fe (accepted)
11392	LINK_EVIDENCE	by 1efd24fe (accepted)
11596	LINK_EVIDENCE	by 1efd24fe (accepted)

Score trace

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