Betelgeuse
Betelgeuse is a red supergiant star in the constellation Orion that changes in brightness over time.
How big is it?
6.511 AU across
Diameter · rounded model
A little perspective
Betelgeuse vs Neptune’s orbital distance: length comparison
Neptune’s orbital distance is about 4.62 times the diameter of Betelgeuse.
Betelgeuse is a red supergiant star in the constellation Orion that changes in brightness over time.
Neptune’s orbital distance is the average separation between Neptune and the Sun.
Both rulers start at the same zero and share one linear scale. Artwork keeps its original proportions. A ruler represents the selected distance or a measurement not visible in this view.
Measurements, assumptions & sources +
Betelgeuse
Diameter: 6.511 AU; rounded model.
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.
Neptune’s orbital distance
Distance: 30.11 AU; rounded reference.
A rounded 30.11 AU semi-major-axis reference, not today’s distance.
Defined examples — our methodology
The marked distance is calibrated. Unmeasured illustration details are representative.
Use the visual comparison to explore its scale, then check the measurements and sources.
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Why this measurement?
Why we use 6.511 AU
We compare the diameter of Betelgeuse. This is an illustrative comparison value, not a claim that every example is the same.
A deliberately rounded red-supergiant model. Its apparent edge varies with wavelength and the star changes over time.
The marked horizontal span follows the measured feature, not the edges of the image. How calibrated comparisons work →
Recorded properties
Dimensions and measurements
| Property | Selected value | Recorded range | Basis |
|---|---|---|---|
| 6.511 AU | Not recorded | rounded model | |
| 15 M☉ | Not recorded | rounded model |
Around this scale
Explore nearby values.
Compare examples with lower, similar and higher values. Each card names the measurement being compared.
Nearest lower valuePlanets, moons and spaceEarth–Sun distance1 AUDistanceThe Earth–Sun distance, or astronomical unit, is the standard measure of separation between Earth and the Sun used in astronomy.Nearest higher valuePlanets, moons and spaceNeptune’s orbital distance30.11 AUDistanceNeptune’s orbital distance is the average separation between Neptune and the Sun.Sources and method
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The source records and measurement method remain available for inspection.
More ways to see it
Curated comparisons
There’s always another scale
Follow your curiosity.
SpaceSun1,391,000 kmThe Sun is the star at the centre of the Solar System.
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.SpaceNeptune’s orbital distance30.11 AUNeptune’s orbital distance is the average separation between Neptune and the Sun.SpaceEarth–Sun distance1 AUThe Earth–Sun distance, or astronomical unit, is the standard measure of separation between Earth and the Sun used in astronomy.
SpaceRed giant0.465 AUA red giant is a star that has expanded and cooled after exhausting the hydrogen in its core.
SpaceKuiper Belt outer orbit50 AUThe Kuiper Belt is a region of the Solar System beyond Neptune containing many icy bodies and dwarf planets.
SpacePlanetary Solar System60.22 AUThe Solar System is the collection of the Sun and all objects gravitationally bound to it, including planets, moons, and smaller bodies.