Earth
Earth is the rocky planet on which we live and the third planet from the Sun.
12,740 kmMean diameterWorlds apart
Earth vs Neutron star
What are they, and what does the difference actually look like?
Two things. One honest scale.
Meet the pair
What these two things are
Neutron star
A neutron star is the dense remnant core left after a massive star explodes as a supernova, composed mostly of neutrons.
20 kmDiameterThe mean diameter of Earth is about 637 times the diameter of Neutron star.
01
Earth12,740 kmMean diameter
02
Neutron star20 kmDiameter
Inset ×221Neutron star is too small to see clearly at this scale. The ring marks its position; only the inset is enlarged.
Measurements, assumptions & sources +
Earth
Mean-radius spherical model for Earth; actual shape is not perfectly spherical.
NASA JPL — planetary physical parameters
The marked mean diameter is calibrated. Unmeasured illustration details are representative.
Neutron star
A 20 km, 1.4 solar-mass teaching model. The precise radius depends on stellar mass and the uncertain behaviour of dense matter.
The marked diameter is calibrated. Unmeasured illustration details are representative.
Change the comparison
Put something else beside it.
Measurement details
Why these numbers?
The visual compares mean diameter with diameter. The records below preserve each value’s basis and caveats.
Earth
12,740 kmMean diameter · approximate
Mean-radius spherical model for Earth; actual shape is not perfectly spherical.
Neutron star
20 kmDiameter · representative
A 20 km, 1.4 solar-mass teaching model. The precise radius depends on stellar mass and the uncertain behaviour of dense matter.
- Comparing
- Mean diameter ↔ Diameter
- Relative size
- Earth is larger on this measurement by a factor of about 637.
How to read the visual
The labelled spans and stored measurements determine the scale; unmeasured illustration details do not.
- Earth is labelled approximate; treat the displayed value as a comparison anchor rather than false precision.
- Neutron star is labelled representative; treat the displayed value as a comparison anchor rather than false precision.
There’s always another scale
Follow your curiosity.
SpaceEarth12,740 kmEarth is the rocky planet on which we live and the third planet from the Sun.SpaceNeutron star20 kmA neutron star is the dense remnant core left after a massive star explodes as a supernova, composed mostly of neutrons.
SpaceMoon3,475 kmThe Moon is Earth’s natural satellite and the brightest large object in Earth’s night sky.
SpaceJupiter139,800 kmJupiter is a giant planet composed mainly of hydrogen and helium, orbiting the Sun beyond the asteroid belt.
SpaceSun1,391,000 kmThe Sun is the star at the centre of the Solar System.
SpaceWhite dwarf12,000 kmA white dwarf is the dense, hot remnant core left behind after a star like the Sun has exhausted its nuclear fuel and shed its outer layers.
Fundamental physicsProton1.682 fmA proton is a positively charged particle found in the nucleus of atoms, made up of quarks.Side by side
Another point of view.
