Likely False· StrongPseudoscience

the earth is flat

The claim that the Earth is flat is decisively contradicted by all available scientific evidence. Geodesy, satellite observations, climate modeling, and direct imaging confirm Earth is an oblate spheroid.

Largest vulnerability: Moderate uncertainty — risk of bias is the main limit: 100% of evidence is opinion/anecdote-tier.

Sources (25)

Geodesy and metrology with a transportable optical clock
Nature Physics · peer_reviewed · 2018-02-09 · credibility 95%
Equatorial radius of the Earth: A dynamical determination | Bulletin Géodésique (1946-1975) | Springer Nature Link
link.springer.com · peer_reviewed · 2008-11-07 · credibility 95%
The determination of the radius of the earth and other geodetic parameters as derived from optical satellite data | Bulletin Géodésique (1946-1975) | Springer Nature Link
link.springer.com · peer_reviewed · 2009-01-08 · credibility 95%
(untitled)
link.springer.com · peer_reviewed · credibility 95%
Earth Observations from DSCOVR/EPIC Instrument - PMC
pmc.ncbi.nlm.nih.gov · peer_reviewed · credibility 95%
A round Earth for climate models
pmc.ncbi.nlm.nih.gov · peer_reviewed · credibility 95%
Mental models of the earth: A study of conceptual change in childhood
Cognitive Psychology · peer_reviewed · 1992-10-01 · credibility 90%
Defining the form of the Earth with the help of pendulums in 1765–1815 | GEM - International Journal on Geomathematics | Springer Nature Link
link.springer.com · peer_reviewed · 2025-02-12 · credibility 90%
Estimating global geodetic parameters using SLR observations to Galileo, GLONASS, BeiDou, GPS, and QZSS | Earth, Planets and Space | Springer Nature Link
link.springer.com · peer_reviewed · 2019-02-18 · credibility 90%
Geodesy, Figure of the Earth | Springer Nature Link
link.springer.com · peer_reviewed · credibility 90%
Visually discerning the curvature of the Earth - PubMed
pubmed.ncbi.nlm.nih.gov · peer_reviewed · credibility 90%
[0812.3911v2] Sunsets, tall buildings and the Earth's radius
arxiv.org · peer_reviewed · 2008-12-20 · credibility 85%
Disinformation and Echo Chambers: How Disinformation Circulates on Social Media Through Identity-Driven Controversies
Journal of Public Policy & Marketing · peer_reviewed · 2022-05-18 · credibility 85%
Earth’s Radius from a Single Sunrise Image: A Classroom-Ready Activity
arxiv.org · peer_reviewed · credibility 80%
Heaven and Earth in Ancient Greek Cosmology: From Thales to Heraclides Ponticus | Springer Nature Link
link.springer.com · peer_reviewed · credibility 80%
When the Earth Was Flat: Studies in Ancient Greek and Chinese Cosmology | Springer Nature Link
link.springer.com · peer_reviewed · credibility 80%
The Dodecahedron, or the Shape of the Earth According to Plato | Springer Nature Link
link.springer.com · peer_reviewed · credibility 80%
Aristotle’s Arguments for the Sphericity of the Earth
link.springer.com · peer_reviewed · credibility 80%
[2003.08541] Meteorology and Oceanography on a Flat Earth
ar5iv.labs.arxiv.org · peer_reviewed · credibility 75%
The “Global” Deception: Flat-Earth Conspiracy Theory between Science and Religion
mdpi.com · peer_reviewed · 2024-03-25 · credibility 75%
(untitled)
arxiv.org · peer_reviewed · credibility 70%
The<i>Gaia</i>mission
Astronomy and Astrophysics · report · 2016-09-15 · credibility 50%
Fractional Brownian Motions, Fractional Noises and Applications
SIAM Review · report · 1968-10-01 · credibility 50%
The cosmological constant and dark energy
Reviews of Modern Physics · report · 2003-04-22 · credibility 50%
Geographical Variability of the First Baroclinic Rossby Radius of Deformation
Journal of Physical Oceanography · report · 1998-03-01 · credibility 50%

The competing case

We evaluated the competing case, and here is why it did not hold.

Competing claims we weighed

The Earth appears flat at human scales and local observations, suggesting flat-Earth models may better reflect everyday lived experience than abstract spheroid mathematics.
Geodetic measurements and satellite-derived Earth radius figures contain inherent uncertainties and model-dependent assumptions, meaning the precise shape of the Earth cannot be definitively established.
Satellite images of a spherical Earth are composites or computer-generated models produced by space agencies, and therefore cannot serve as direct observational proof of Earth's shape.
Climate models that assume a spherical Earth introduce systematic biases, implying the spherical assumption is a modelling convenience rather than a confirmed physical reality.

Epistry weighs the case for and against — see the full breakdown, including the opposing evidence and why it held or failed, in the app.