Semantic comparison atlas

Put anything
beside everything.

Browse editorially selected size comparisons across biology, engineering, Earth, planets, stars and the cosmic web, then open the semantic comparison engine.

29
editorial comparisons
5
visual modes
121
available landmarks

Build your own experiment

Choose two coordinates.

Custom combinations open in the interactive engine and are intentionally excluded from search indexing. The permanent comparison pages below are curated, written and canonical.

Permanent comparisons

Questions people actually ask.

Each page keeps measurement definitions, certainty and linear semantics visible.

Visual evidence plate for EarthVisual evidence plate for The Sun109.3×
Planetary ↔ Stellar

How many Earths fit across the Sun?

Compare Earth’s mean diameter with the Sun’s photospheric diameter and see why the star can hold the scale of worlds.

12,742 km1.393 million km
Visual evidence plate for Milky WayVisual evidence plate for Andromeda Galaxy2.199×
Galactic ↔ Galactic

Is Andromeda larger than the Milky Way?

Visible galaxy diameters are diffuse estimates, but the comparison gives useful context for the Local Group’s two dominant spirals.

≈100,000 light-years≈220,000 light-years