Sun
The Sun is the star at the centre of the Solar System.
1,391,000 kmDiameterWorlds apart
Sun vs Betelgeuse
What are they, and what does the difference actually look like?
Two things. One honest scale.
Meet the pair
What these two things are
Betelgeuse
Betelgeuse is a red supergiant star in the constellation Orion that changes in brightness over time.
6.511 AUDiameterBetelgeuse has about 700 times the diameter of Sun.
01
Sun1,391,000 kmDiameter
02
Betelgeuse6.511 AUDiameter
Inset ×241Sun is too small to see clearly at this scale. The ring marks its position; only the inset is enlarged.
Measurements, assumptions & sources +
Sun
Our star, modelled with the IAU nominal solar radius. “Surface” means the visible photosphere. The core is much hotter; this is not a solid surface.
IAU — nominal solar and planetary conversion constants
The marked diameter is calibrated. Unmeasured illustration details are representative.
Betelgeuse
A deliberately rounded red-supergiant model. Its apparent edge varies with wavelength and the star changes over time.
Defined examples — our methodology
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 diameter with diameter. The records below preserve each value’s basis and caveats.
Sun
1,391,000 kmDiameter · approximate
Our star, modelled with the IAU nominal solar radius. “Surface” means the visible photosphere. The core is much hotter; this is not a solid surface.
Betelgeuse
6.511 AUDiameter · rounded model
A deliberately rounded red-supergiant model. Its apparent edge varies with wavelength and the star changes over time.
- Comparing
- Diameter ↔ Diameter
- Relative size
- Betelgeuse is larger on this measurement by a factor of about 700.
How to read the visual
The labelled spans and stored measurements determine the scale; unmeasured illustration details do not.
- Sun is labelled approximate; treat the displayed value as a comparison anchor rather than false precision.
- Betelgeuse is labelled rounded model; treat the displayed value as a comparison anchor rather than false precision.
There’s always another scale
Follow your curiosity.
SpaceSun1,391,000 kmThe Sun is the star at the centre of the Solar System.SpaceBetelgeuse6.511 AUBetelgeuse is a red supergiant star in the constellation Orion that changes in brightness over time.
SpaceEarth12,740 kmEarth is the rocky planet on which we live and the third planet from the Sun.
SpaceJupiter139,800 kmJupiter is a giant planet composed mainly of hydrogen and helium, orbiting the Sun beyond the asteroid belt.
SpaceNeutron star20 kmA neutron star is the dense remnant core left after a massive star explodes as a supernova, composed mostly of neutrons.
SpaceEarth–Sun distance1 AUThe Earth–Sun distance, or astronomical unit, is the standard measure of separation between Earth and the Sun used in astronomy.Side by side
Another point of view.
